Novel USH2A Mutations in Israeli Patients with Retinitis Pigmentosa and Usher Syndrome Type 2

OPHTHALMIC MOLECULAR GENETICS Novel USH2A Mutations in Israeli Patients With Retinitis Pigmentosa and Usher Syndrome Type 2

Nadia Kaiserman, MSc; Alexey Obolensky, MD, PhD; Eyal Banin, MD, PhD; Dror Sharon, PhD

Objective: To identify USH2A mutations in Israeli pa- and a novel missense mutation (Gly4674Arg) had non- tients with autosomal-recessive Usher syndrome type 2 syndromic RP. (USH2) and retinitis pigmentosa (RP). Conclusions: Our results support the involvement of Methods: Patients from 95 families with RP and 4 with USH2A in nonsyndromic RP and we report here of a sec- USH2 were clinically evaluated. USH2A exons 2-72 were ond, novel, missense mutation in this gene causing au- scanned for mutations using single-strand conformation tosomal-recessive RP. and sequencing analyses. The frequency of novel missense changes was determined in patients and controls Clinical Relevance: Possible involvement of USH2A using restriction endonucleases. should be considered in the molecular genetic evalua- Results: The analysis revealed 3 USH2A mutations, tion of patients with autosomal-recessive RP. Under- 2 of which are novel, in 2 families with USH2 and a standing the mechanism by which different USH2A mu- large family (MOL0051) with both USH2 and RP. Com- tations cause either USH2 or RP may assist in the pound heterozygotes for 2 null mutations (Thr80fs and development of novel therapeutic approaches. Arg737stop) in MOL0051 suffered from USH2 while compound heterozygotes for 1 of the null mutations Arch Ophthalmol. 2007;125:219-224

ETINITIS PIGMENTOSA (RP) expressed in additional tissues as well. is a group of progressive Recent studies suggest that usherin is rod-cone degenerations integrated into a protein network formed characterized by night by other USH-causing proteins.8,9 USH2A blindness followed by can produce a short isoform (encoded by visual-field loss, resulting in severe visual exons 2-21) and long isoforms produced R 10 impairment. Most patients have no asso- by alternative splicing of exons 2-72. ciated systemic disease (nonsyndromic More than 50 pathogenic mutations have 11-19 RP) while others suffer from associated been reported so far in exons 2-21 and 5 mutations were reported in exons extraocular diseases. The most common 10 syndromic RP is Usher syndrome, with 22-72. Interestingly, 1 missense muta- an estimated prevalence of 5:100 000 live tion, Cys759Phe, is responsible for births.1 Usher syndrome can be catego- approximately 7% of nonsyndromic rized into 3 clinical types: patients with autosomal-recessive RP (ARRP) cases, suggesting that under certain conditions Usher type 1 (USH1) typically have con- USH2A can cause RP without hearing genital deafness, vestibular ataxia, and loss.14,18 We report here the identification night blindness noted in the first or sec- of novel USH2A mutations causing USH2 ond decade, whereas in USH2, night and nonsyndromic RP in the Israeli blindness appears in the second to fourth population. decade, accompanied by moderate early- onset hearing loss and no ataxia.2,3 Usher type 3 is found mostly among Finnish patients with onset of progressive hear- METHODS ing loss and RP in the late teens and vari- able vestibular dysfunction.4 At least 3 genetic USH2 loci were Index patients from 95 Jewish and Muslim Is- identified with USH2A being the most raeli families with ARRP and 4 with USH2 were Author Affiliations: recruited for this study. All patients under- Department of Ophthalmology, common, responsible for approximately went clinical evaluation that included full oph- 5,6 Hadassah-Hebrew University 85% of USH2 cases. USH2A encodes thalmologic examination, assessment of re- Medical Center, for usherin, a basement membrane pro- fractive error, visual field testing, color vision Jerusalem, Israel. tein in the inner ear and retina,7 and is testing, and full-field electroretinography

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1234567891011121314 II

123456789 10 11 12 13 14 15 16 17 18 19 III 7 7 3 4 9 4

B MOL0051 MOL0165 MOL0035 12 1 2 12 78 I I II

– – + – T80fs 1 1 1 2 A125T 2 2 2 1 T473T 1 1 1 2 IVS9+33 + – – – R373X 1234 12 34 – – – + R4674G II II R373X/ T80fs/ 4569 10 12 R373X + III – + – + – – – + – – + – 1 1 1 1 1 2 1 1 2 2 1 2 2 2 2 2 2 1 2 2 1 1 2 1 1 1 1 1 1 2 1 1 1 2 1 2 + – + – + – + – – – – – – – – – – + – – – + – +

Figure 1. Israeli families with USH2A mutations. A, Family MOL0051. B, Single nucleotide polymorphisms and USH2A mutations in 3 Israeli families. Gray filling denotes retinitis pigmentosa and black filling denotes Usher syndrome type 2. Numbers above symbols indicate recruited individuals and numbers within diamonds indicate the number of siblings. A slash over an individual symbol indicates that person is deceased.

(ERG). All patients had typical RP changes to varying degrees (MOL0051) was the focus of the study, presenting a com- and full-field ERG confirmed various levels of rod more than plex inheritance pattern in which some family members cone dysfunction. Patients with USH2 reported partial hear- suffered from USH2 while others had nonsyndromic RP ing loss, which was tested clinically and verified by audiom- (Figure 1A). MOL0051 is of Iraqi Jewish origin with etry when required. Patients with nonsyndromic ARRP were no clear pattern of disease inheritance, but consanguin- asked about hearing problems and additional testing was performed if hearing impairment was suspected. The tenets of the ity in some branches of the family would suggest an au- Declaration of Helsinki were followed and informed consent tosomal-recessive inheritance. In the nuclear family, the was obtained from all patients who participated in this study mother (II-2) has 1 brother with USH2 and 3 siblings with prior to donation of a blood sample. RP. Three of her children manifest USH2 while 3 others The single-strand conformation polymorphism technique were diagnosed with RP (Figure 1A). At the age of 66 was used to screen genomic DNA for mutations in exons 2-21 years, she had advanced RP, including nonrecordable ERG and to perform haplotype analysis using single nucleotide poly- responses and severely constricted visual fields morphisms. Mutation analysis of exons 22-72 was done by se- (Figure 2A and B), while her audiometry findings were quencing of polymerase chain reaction products (primer se- normal. Her 3 daughters with RP (aged 32-39 years) had quences are available on request). The frequencies of missense changes were tested in 94 ARRP index cases and 10 unrelated somewhat less severe retinal disease, but all were legally controls using restriction enzymes (MboII for C759F, Hpy188I blind, as shown in the representative clinical data of pa- for I1665T, TspRI for R2875Q, BtsI for N3099S, BfuCI and tient III-6 (Figure 2A and C). The youngest son (III-9) Sau3AI for D3144N, NdeI for I3335M, FokI and HpaII for with USH2 still had residual cone responses on ERG, but R4674G). In 2 sequence changes (I1665T and R4674G), where in his 2 older siblings with USH2, ERGs were nonrecord- no restriction enzyme could distinguish between the wild- able (Figure 2A). All 3 were found to have mild to mod- type and the mutant alleles, we designed a primer located ad- erate hearing loss in early childhood (a representative au- jacent to the sequence change and included a base change in diogram of patient III-4 at the age of 38 years is shown the primer sequence to create a restriction site. in Figure 2E). The visual field findings as well as fundus photograph and autofluorescence image for this patient RESULTS are shown in Figure 2D, F, and G (note residual ring of hyperfluorescence in macular area surrounded by large We studied the involvement of USH2A in 44 families with patches of hypofluorescence corresponding to areas of ARRP and 4 families with USH2. One of these families atrophy).

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©2007 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/28/2021 A Pt No. Diagnosis Age, y VA (OD OS) Cone Flicker Mixed ERG Rod ERG EOG Arden Color Vision ERG, µV, ms a, b Waves, µV b Wave, µV Ratio, %

III-6 RP 34 6/6 24, 39 29, 40 Extinct 139 Normal 6/7.5 11, 39 17, 50 139

II-2 RP 66 6/27 Extinct Extinct Extinct 100 Tritanopia 6/54 100

III-9 USH2 28 6/15 20, 42 Extinct Extinct 162 Normal 6/15 20, 44 160

III-5 USH2 36 6/18 Extinct Extinct Extinct 106 Normal 6/15 114

III-4 USH2 38 6/15 Extinct Extinct Extinct 111 Tritanopia 6/15 100

Normal Values 6/6 >60, <33 a>100 >200 >185 b>400

120 105 90 75 60 120 105 90 75 60 B C 135 70 45 135 70 45 60 60 150 50 30 150 50 30 40 40 30 30 165 15 165 15 20 20 10 10 90 80 70 60 50 40 30 20 10 10 20 30 40 50 60 70 80 90 90 80 70 60 50 40 30 20 10 10 20 30 40 50 60 70 80 90 10 10 20 195 195 20 30 345 30 345 40 40 210 50 330 210 50 330 60 60 225 70 315 225 70 315

240255 270 285 300 Pt II-2240255 270 285 300 Pt III-6 120 105 90 75 60 D E –10 135 70 45 60 0 150 50 30 10 40 20 30 165 15 20 30 10 40 90 80 70 60 50 40 30 20 10 10 20 30 40 50 60 70 80 90 50 dB 10 60 195 20 30 345 70 40 80 210 50 330 90 60 100 225 70 315 110 240255 270 285 300 Pt III-4 250 500 1000 2000 4000 8000 Hz

F G

Figure 2. Affected members of family MOL0051 manifest either retinitis pigmentosa (RP) or Usher syndrome type 2 (USH2). A, Visual acuity (VA), electroretinographic (ERG), electro-oculographic (EOG), and color vision testing findings. B and C, Marked constriction of Goldman visual fields in the 66-year-old mother (B) and her 34-year-old daughter (C) with RP. Black isopter indicates target V4e; green, III4e; blue, I4e. D-G: Visual field findings (D), audiometry results (E), fundus photograph (F), and autofluorescence image (G) of the 38-year-old son with USH2 (patient III-4). Pt indicates patient.

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Source DNA Change* Exon Protein Change Mutation Type Frequency† Pathogenic Mutations Adato et al17 239-242insCGAT 2 Thr80fs Frameshift 3.1 Novel 2209CϾT (CGAϾTGA) 13 Arg737Stop Nonsense 4.2 Nonpathogenic Mutations Weston et al,16 Adato et al17 373GϾA (GCAϾACA) 2 Ala125Thr Missense 36.5 Seyedahmadi et al,14 Weston et al,16 Adato et al17 1419CϾT (ACCϾACT) 8 Thr473Thr Silent 17.7 Seyedahmadi et al,14 Weston et al,16 Adato et al17 1434GϾC (GAGϾGAC) 8 Glu478Asp Missense 1.0 Novel IVS9 ϩ 33a Ͼ c Int9 None Intronic 17.7 Novel IVS9 ϩ 40g Ͼ a Int9 None Intronic 16.7 Weston et al,16 Adato et al17 1931AϾT (GATϾGTT) 11 Asp644Val Missense 19.8 Weston et al,16 Adato et al17 2109TϾC (GATϾGAC) 12 Asp703Asp Silent 1.0 Dreyer et al20 2137GϾC (GGCϾCGC) 12 Gly713Arg Missense 6.3 Novel IVS13-19insA Int17 None Intronic 2.1 Novel IVS17-13delT Int17 None Intronic 1.0 Novel IVS18-8t Ͼ g Int18 None Intronic 14.6 Novel IVS20-33-36delCTTT Int20 None Intronic 1.0 Weston et al,16 Adato et al17 4457AϾG (AAGϾAGG) 21 Lys1486Arg Missense 33.3

*Nucleotide positions are based on accession number NM_206933. †Allele frequency evaluated from a group of 88 autosomal-recessive retinitis pigmentosa alleles and 8 Usher syndrome type 2 alleles.

Table 2. Novel Sequence Changes in USH2A Exons 22-72

Protein Mutation Protein Allele Frequency, Base Change Exon Change Type Domain ARRP, Control* 4994TϾC(ATCϾACC) 25 I1665T Missense LamG 69:31, 60:40 IVS25 ϩ 33t Ͼ a Int25 None Intronic 6317TϾC (ATAϾACA) 32 I2106T Missense None 6506TϾC (ATAϾACA) 34 I2169T Missense None ND, 27:63 8625GϾA (CGGϾCAG) 43 R2875Q Missense FibIII 100:0, 95:5 9297AϾG (AATϾAGT) 47 N3099S Missense None 98.4:1.6, 90:10 9431GϾA (GATϾAAT) 48 D3144N Missense None 98.4:1.6, 90:10 10014AϾG (ATAϾATG) 51 I3335M Missense None 60:40, 80:20 IVS58 ϩ 14delA Int58 None Intronic 11946GϾA (CTGϾCTA) 61 L3983L Silent 12612AϾG (ACAϾACG) 63 T4204T Silent 12666AϾG (ACAϾACG) 63 T4222T Silent 13491GϾA (GAGϾGAA) 63 E4408E Silent 14021AϾG (AGAϾGGA) 64 R4674G Missense FibIII 100:0, 100:0

Abbreviations: ARRP, autosomal-recessive retinitis pigmentosa; FibIII, fibronectin type 3; LamG, laminin G domain; ND, not done. *Wild-type vs novel allele frequency in 188 ARRP chromosomes and 20 control chromosomes.

The segregation of both USH2 and RP in the same pedi- members of family MOL0051. The analysis revealed 15 se- gree prompted us to study the possible involvement of quence changes, 2 of which are pathogenic (Table 1): a USH2A by performing a haplotype analysis using 3 single 4 base pair insertion (Thr80fs)17 and a novel nonsense mu- nucleotide polymorphisms located within USH2A tation (Arg737stop). Each of these mutations was identi- (Ala125Thr, Thr473Thr, and IVS9ϩ33AϾC; Figure 1B). fied in 2 families: Thr80fs was found heterozygously in pa- The father (II-1) carried 2 identical haplotypes and was non- tients from families MOL0051 and MOL0035, and informative. His wife (II-2) carried 2 different haplotypes, Arg737stop was found heterozygously in patients from which cosegregated with the phenotypes: haplotype 1-2-1 MOL0051 and homozygously in MOL0165-1 (Figure 1B). was inherited by the 3 children with USH2 while haplo- All patients with USH2 in MOL0051 were compound het- type 2-1-2 was inherited by her daughter with RP (III-5). erozygotes for the 2 null mutations while patients with RP This cosegregation is also supported by a relative with RP were heterozygotes for either the nonsense or the frame- (III-12) who shares the same haplotypes with II-2. shift mutation (Figure 1B). No mutations in exons 2-21 were identified on the RP-specific maternal allele. The only MUTATION ANALYSIS OF EXONS 2-21 ARRP-associated USH2A mutation reported so far, Cys759Phe,18 was absent in our cohort of 95 ARRP and 4 We performed a mutation analysis of exons 2-21 in 48 in- USH2 families. In 2 families (MOL0051 and MOL0035), dex cases, including 44 with ARRP, 3 with USH2, and 2 we did not identify all expected pathogenic mutations. In

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©2007 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/28/2021 I1665T I2106T Homo sapiens LRKD---PEIIQKGFVGCLKD Homo sapiens LIYSGSEENYIVTDLAVFTPH Pan troglodytes LRKD---PEIIQKGFVGCLKD Canis familiaris LIYSGSGENYTVTDLAVFTPH Canis familiaris LRKD---PDIIQKGFVGCVKD Mus musculus LVYTGKGQNYTVTDLRVFTAY Mus musculus LQKR---LEIIQRGFVGCLKD Rattus norvegicus LVYTGKGQNYTVT------Rattus norvegicus LQKR---PEIVRRGFVGCLKD Danio rerio VLYRGNSTSFNITDVGVFTPH Gallus gallus VRRDEGMKMVIQKGFVGCLSD ::* *. .: :* Danio rerio LRQDAGQAKLVQQGFAGCLRD ::: ::::**.**: *

I2169T R2875Q Homo sapiens IHIQWKQPRKISGILERYVLY Homo sapiens LASNPPEDLNRWHNIYSGTQW Bos taurus VYIQWKQPRKVNGILERYMLY Pan troglodytes LASNPPEDLNRWHNIYSGTQW Canis familiaris IHVRWKQPRQLNGILERYILY Canis familiaris LASNPPEDLNLWHNIYSGTQW Mus musculus IHVRWKQPRQLNGILERYILY Mus musculus LASNPPEDLNLWHNIYSGTRW Rattus norvegicus VHIQWKQPRQLNGILERYILY Rattus norvegicus LASNPPEDLNLWHNIYSGTRR Gallus gallus IYVQWKEPLELNGILDRYVIY Gallus gallus LASNPPEDLNLWHNIYSGTQW Danio rerio IHIQWAAPVEVNGLLEFYTLH Danio rerio LASRPPEDFNLWYNVYAGTKL ::::* * ::.*:*: * :: ***.****:* *:*:*:**:

N3099S D3144N Homo sapiens VCTIYACVKSNGTQITTVEDT Homo sapiens RKPNGIILGYDLLWKTWYPCA Pan troglodytes VCTIYACVKSNGTQITTVEDT Pan troglodytes RKPNGIILGYDLLWKTWYPCT Canis familiaris VCTKYACVKSNGTQFTTVEDT Mus musculus ANPNGIILGYDVLRKTWRPCS Mus musculus VCTKDACVKSNGTQVSTAEDT Rattus norvegicus GNPNGIILGYDVLRKTWRLCS Rattus norvegicus VCTKDACVKSSGTQVSTAEDT Gallus gallus RQPNGIILGYEVLRKAFKRC- Gallus gallus ACTVYACVRSNGTQITTVEDE Canis familiaris GKPNGIILGYDLLRKKHS-CP Danio rerio VCTVYACVKSNSTQVTTVEDT :********::* * * .** ***:*..**.:*.**

I3335M R4674G Homo sapiens GQDYVNMSDTICCSASSGESK Homo sapiens NGKVLYYELYRRQIATQPRKS Canis familiaris GQDYVNMSDTICCSASSGESK Pan troglodytes NGKVLYYELYRRQIATQPGKS Mus musculus GQDYVNMSETICCSASSGESK Canis familiaris NGKVIYYELYRRQIAAHPGKS Rattus norvegicus GQDYVNMSDTICCSASSGDSK Mus musculus NGKIICFELYRRQVAAWPGTS Gallus gallus GQEYVNVSDTICCSGSSGESL Rattus norvegicus HGKIVRFELYRRQTASWPGTS Danio rerio GEHYINTSTSWCCTGPGGESK Gallus gallus NGKILHYELYRRRMTQALINL *:.*:* * : **:...*:* Danio rerio NGKLLHYELYRKHLSDMESRS :**:: :****:: :

Figure 3. Multiple sequence alignment of regions spanning novel missense changes in the long usherin isoform. Arrows indicate mutation position. In the color coding of amino acids, red indicates small residues; blue, acidic; magenta, basic; green, hydroxyl, amine, and basic; and gray, other residues.

MOL0035 only 1 of the 2 mutations was identified and in RP. Both were heterozygote for all 6 changes, indicating MOL0051 2 of the 3 were identified. Sequencing analysis that they are located on the RP-associated allele. Sec- of exons 2-21 in members of these families did not reveal ond, we examined the location of the 7 changes along any additional sequence changes. the long usherin isoform and identified 3 changes (I1665T, R2875Q, and R4674G) located within functional do- MUTATION ANALYSIS OF EXONS 22-72 mains (Table 2). Third, we aligned USH2A sequences from different species for each of the studied substitutions, 6 To identify the remaining USH2A pathogenic muta- of which were evolutionary conserved (I1665T, R2875Q, tions, we performed a sequencing analysis of exons 22-72 N3099S, D3144N, I3335M, and R4674G; Figure 3). in families MOL0051 and MOL0035. We identified 14 However, the only perfectly conserved residue was novel sequence changes (Table 2), none of which is likely Arg4674, which was identical in all species. Finally, we to create or destroy a splice site. Thirteen sequence studied the allele frequency of the candidate sequence changes were found in a heterozygous state while changes in patients with ARRP and controls. The analy- 6317TϾC (I2106T) was homozygous in patients from sis revealed that all missense changes except R4674G were both families. In addition, a human expressed sequence prevalent in both groups (Table 2), excluding these tag (AA883599) and all available orthologs have a cyto- changes as disease-causing mutations. The R4674G mu- sine at position 6317, indicating that I2106T is a com- tation was not found in either group and is therefore spe- mon polymorphism in humans with threonine at posi- cific to the RP-associated allele in MOL0051. tion 2106 being the ancestral allele. To determine which of the 7 remaining missense changes is pathogenic, we studied different aspects of these COMMENT changes. First, since 6 of the missense changes were found in MOL0051, we correlated them to the haplotypes by We describe here 3 USH2A mutations in patients with USH2 sequencing the corresponding exons in 2 patients with and ARRP. Two of the mutations are null and can be found

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©2007 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/28/2021 in patients with either phenotype while a novel missense Author Contributions: Drs Banin and Sharon contrib- mutation, R4674G, is specific to the RP phenotype and uted equally to this work. is likely to be pathogenic. This is the second USH2A mu- Financial Disclosure: None reported. tation thus far reported to cause ARRP and the first to be Funding/Support: The study was supported by the identified on the long isoform. This indicates that the mu- Israeli Ministry of Sciences (grant No. 5807) and by the tation interferes with the function of usherin in a retina- Yedidut Research Grant. specific manner, perhaps affecting its interactions with Acknowledgment: We thank the patients and their fami- retina-specific proteins while sparing the auditory system. lies for participating in the study. We thank Liliana The first RP-causing mutation reported in USH2A, Mizrahi-Meissonnier, Ruhama Neis, and Israel Barzel for Cys759Phe, was found in approximately 7% of ARRP excellent technical assistance. cases.14,18 Another study, however, reported that 2 individuals homozygotes to Cys759Phe have no retinal or hear- 21 ing problems, raising the possibility that Cys759Phe is REFERENCES in linkage disequilibrium with another, currently un- 10 known, mutation. Unlike previous reports, Cys759Phe 1. Rosenberg T, Haim M, Hauch AM, Parving A. The prevalence of Usher syn- could not be identified in our cohort of 95 patients with drome and other retinal dystrophy-hearing impairment associations. Clin Genet. ARRP (PϽ.05), suggesting a low frequency in the Israeli 1997;51:314-321. population. Two of the mutations identified in the cur- 2. Smith RJ, Berlin CI, Hejtmancik JF, et al. Clinical diagnosis of the Usher syn- dromes: Usher Syndrome Consortium. Am J Med Genet. 1994;50:32-38. rent study are novel, and the third was reported previ- 3. Tsilou ET, Rubin BI, Caruso RC, et al. Usher syndrome clinical types I and II . 17 ously only in 1 Iranian Jewish family. All 3 mutations are Acta Ophthalmol Scand. 2002;80:196-201. therefore likely to be unique to Jews originating from the 4. Sankila EM, Pakarinen L, Kaariainen H, et al. Assignment of an Usher syndrome same region (Iran-Iraq-Bukhara-Afghanistan). This is in type III (USH3) gene to chromosome 3q. Hum Mol Genet. 1995;4:93-98. 5. Kimberling WJ, Weston MD, Moller C, et al. Gene mapping of Usher syndrome agreement with other mutations causing Usher syn- type IIa. Am J Hum Genet. 1995;56:216-223. drome, which were found to be relatively common and re- 6. Eudy JD, Weston MD, Yao S, et al. Mutation of a gene encoding a protein with stricted to specific Jewish subpopulations.22,23 extracellular matrix motifs in Usher syndrome type IIa. Science. 1998;280: We identified 14 novel sequence changes in exons 22-72 1753-1757. in patients with ARRP. Six of them were missense changes 7. Bhattacharya G, Miller C, Kimberling WJ, Jablonski MM, Cosgrove D. Localiza- tion and expression of usherin. Hear Res. 2002;163:1-11. located on a single RP-associated allele and therefore could 8. Adato A, Lefevre G, Delprat B, et al. Usherin, the defective protein in Usher syn- potentially be responsible for the disease. We were able to drome type IIA, is likely to be a component of interstereocilia ankle links in the exclude 5 of these changes as pathogenic: I2106T was not inner ear sensory cells. Hum Mol Genet. 2005;14:3921-3932. conserved along evolution; I1665T, I3335M, N3099S, and 9. Reiners J, van Wijk E, Marker T, et al. Scaffold protein harmonin (USH1C) pro- vides molecular links between Usher syndrome type 1 and type 2. Hum Mol Genet. D3144N were polymorphisms (common in controls as well 2005;14:3933-3943. as patients). In contrast, the R4674G mutation was found 10. van Wijk E, Pennings RJ, te Brinke H, et al. Identification of 51 novel exons of only on the RP-associated allele in MOL0051 and was nega- the Usher syndrome type 2A (USH2A) gene that encode multiple conserved func- tive in 208 chromosomes of patients with ARRP and con- tional domains and that are mutated in patients with Usher syndrome type II. trols, indicating that it is a rare variant. In addition, the ar- Am J Hum Genet. 2004;74:738-744. 11. Bernal S, Meda C, Solans T, et al. Clinical and genetic studies in Spanish pa- ginine residue in position 4674 is perfectly conserved in a tients with Usher syndrome type II. Clin Genet. 2005;68:204-214. wide range of organisms (including human, chicken, and 12. Ouyang XM, Hejtmancik JF, Jacobson SG, et al. Mutational spectrum in Usher zebra fish). The combination of a highly conserved resi- syndrome type II. Clin Genet. 2004;65:288-293. due, a conversion of a positively charged amino acid (ar- 13. Pennings RJ, Te Brinke H, Weston MD, et al. USH2A mutation analysis in 70 Dutch families with Usher syndrome type II. Hum Mutat. 2004;24:185. ginine) to a polar amino acid (glycine), and the specific as- 14. Seyedahmadi BJ, Rivolta C, Keene JA, Berson EL, Dryja TP. Comprehensive screen- sociation with the RP-causing allele strongly indicate that ing of the USH2A gene in Usher syndrome type II and non-syndromic recessive this mutation is pathogenic. The pathogenicity of this mis- retinitis pigmentosa. Exp Eye Res. 2004;79:167-173. sense change will have to be verified once a functional test 15. Leroy BP, Aragon-Martin JA, Weston MD, et al. Spectrum of mutations in USU2A for usherin is available. in British patients with Usher syndrome type II. Exp Eye Res. 2001;72:503-509. 16. Weston MD, Eudy JD, Fujita S, et al. Genomic structure and identification of novel In conclusion, our findings support the need to con- mutations in usherin, the gene responsible for Usher syndrome type IIa. Am J sider possible involvement of the USH2A gene not only Hum Genet. 2000;66:1199-1210. in patients with Usher syndrome but also in patients with 17. Adato A, Weston MD, Berry A, Kimberling WJ, Bonne-Tamir A. Three novel mu- nonsyndromic ARRP. In addition, understanding the tations and twelve polymorphisms identified in the USH2A gene in Israeli USH2 families. Hum Mutat. 2000;15:388. mechanism that causes the disease to be limited only to 18. Rivolta C, Sweklo EA, Berson EL, Dryja TP. Missense mutation in the USH2A the retina may afford new insights into the pathogenesis gene. Am J Hum Genet. 2000;66:1975-1978. and can assist in the development of novel therapeutic 19. Dreyer B, Tranebjaerg L, Rosenberg T, Weston MD, Kimberling WJ, Nilssen O. approaches for these blinding diseases. Identification of novel USH2A mutations. Eur J Hum Genet. 2000;8:500-506. 20. Dreyer B, Tranebjaerg L, Brox V, et al. A common ancestral origin of the fre- quent and widespread 2299delG USH2A mutation. Am J Hum Genet. 2001; Submitted for Publication: June 30, 2006; final revi- 69:228-234. sion received September 13, 2006; accepted September 21. Bernal S, Ayuso C, Antinolo G, et al. Mutations in USH2A in Spanish patients 20, 2006. with autosomal recessive retinitis pigmentosa. J Med Genet. 2003;40:e8. Correspondence: Dror Sharon, PhD, Department of Oph- 22. Ben-Yosef T, Ness SL, Madeo AC, et al. A mutation of PCDH15 among Ashkenazi Jews with the type 1 Usher syndrome. N Engl J Med. 2003;348:1664-1670. thalmology, Hadassah-Hebrew University Medical Cen- 23. Ness SL, Ben-Yosef T, Bar-Lev A, et al. Genetic homogeneity and phenotypic vari- ter, PO Box 12000, Jerusalem 91120, Israel (drorsharon ability among Ashkenazi Jews with Usher syndrome type III. J Med Genet. 2003; @md.huji.ac.il). 40:767-772.

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©2007 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/28/2021 Submitted for Publication: August 30, 2006; final revi- 9. Nakagami T, Yamazaki Y, Hayamizu F. Prognostic factors for progression of vision received December 3, 2006; accepted January 8, 2007. sual field damage in patients with normal-tension glaucoma. Jpn J Ophthalmol. 2006;50(1):38-43. Correspondence: Young Jae Hong, MD, PhD, Depart- 10. Kass MA, Kolker AE, Becker B. Prognostic factors in glaucomatous visual field ment of Ophthalmology, Severance Hospital, Yonsei loss. Arch Ophthalmol. 1976;94(8):1274-1276. University College of Medicine, 134 Shinchon-dong, 11. Werner EB, Drance SM. Progression of glaucomatous field defects despite suc- Seodaemun-gu, Seoul, 120-752 Korea (yjhong0815@yumc cessful filtration. Can J Ophthalmol. 1977;12(4):275-280. .yonsei.ac.kr). 12. Chauhan BC, Drance SM. The relationship between intraocular pressure and visual field progression in glaucoma. Graefes Arch Clin Exp Ophthalmol. 1992; Financial Disclosure: None reported. 230(6):521-526. 13. Smith J. Diurnal intraocular pressure: correlation to automated perimetry. REFERENCES Ophthalmology. 1985;92(7):858-861. 14. Rota-Bartelink AM, Pitt A, Story I. Influence of diurnal variation on the intraocular pressure measurement of treated primary open-angle glaucoma during of- 1. Mao LK, Stewart WC, Shields MB. Correlation between intraocular pressure con- fice hours. J Glaucoma. 1996;5(6):410-415. trol and progressive glaucomatous damage in primary open-angle glaucoma. Am 15. Saccà SC, Rolando M, Marletta A, Macri A, Cerqueti P, Ciurlo G. Fluctuations of J Ophthalmol. 1991;111(1):51-55. intraocular pressure during the day in open-angle glaucoma, normal-tension glau- 2. Bergea˚ B, Bodin L, Svedbergh B. Impact of intraocular pressure regulation on coma and normal subjects. Ophthalmologica. 1998;212(2):115-119. visual fields in open-angle glaucoma. Ophthalmology. 1999;106(5):997-1005. 16. Caporossi A, Casprini F, Tosi GM, Balestrazzi A. Long-term results of combined 3. The AGIS Investigators. The Advanced Glaucoma Intervention Study (AGIS), 7: the relationship between control of intraocular pressure and visual field 1-way phacoemulsification, intraocular lens implantation, and trabeculectomy. deterioration. Am J Ophthalmol. 2000;130(4):429-440. J Cataract Refract Surg. 1999;25(12):1641-1645. 4. Heijl A, Leske MC, Bengtsson B, Hyman L, Bengtsson B, Hussein M; Early Mani- 17. Kuroda S, Mizoguchi T, Terauchi H, Nagata M. Trabeculectomy combined with fest Glaucoma Trial Group. Reduction of intraocular pressure and glaucoma pro- phacoemulsification and intraocular lens implantation. Semin Ophthalmol. 2001; gression: results from the Early Manifest Glaucoma Trial. Arch Ophthalmol. 2002; 16(3):168-171. 120(10):1268-1279. 18. Advanced Glaucoma Intervention Study, 2: visual field test scoring and reliability. 5. Brogliatti B, Rigault R, Palanza L, et al. Intraocular pressure and progression of Ophthalmology. 1994;101(8):1445-1455. visual field damage. Acta Ophthalmol Scand Suppl. 2002;236:26-27. 19. Gardiner SK, Crabb DP. Examination of different pointwise linear regression meth- 6. Leske MC, Heijl A, Hussein M, Bengtsson B, Hyman L, Komaroff E; Early Mani- ods for determining visual field progression. Invest Ophthalmol Vis Sci. 2002; fest Glaucoma Trial Group. Factors for glaucoma progression and the effect of 43(5):1400-1407. treatment: the Early Manifest Glaucoma Trial. Arch Ophthalmol. 2003;121(1): 20. Nouri-Mahdavi K, Caprioli J, Coleman AL, Hoffman D, Gaasterland D. Pointwise 48-56. linear regression for evaluation of visual field outcomes and comparison with 7. Nouri-Mahdavi K, Hoffman D, Coleman AL, et al. Predictive factors for glauco- the advanced glaucoma intervention study methods. Arch Ophthalmol. 2005; matous visual field progression in the Advanced Glaucoma Intervention Study. 123(2):193-199. Ophthalmology. 2004;111(9):1627-1635. 21. Manassakorn A, Nouri-Mahdavi K, Koucheki B, Law SK, Caprioli J. Pointwise lin- 8. Ehrnrooth P, Puska P, Lehto I, Laatikainen L. Progression of visual field defects ear regression analysis for detection of visual field progression with absolute and visual loss in trabeculectomized eyes. Graefes Arch Clin Exp Ophthalmol. versus corrected threshold sensitivities. Invest Ophthalmol Vis Sci. 2006;47 2005;243(8):741-747. (7):2896-2903.

Correction

Error in Acknowledgment. In the Ophthalmic Molecu- lar Genetics article titled “Novel USH2A Mutations in Is- raeli Patients With Retinitis Pigmentosa and Usher Syn- drome Type 2,” published in the February 2007 issue of the Archives (2007;125[2]:219-224), the Funding/ Support section should have appeared as follows: “The study was supported by the Chief Scientist at the Israeli Ministry of Health (grant No. 5807) and by the Yedidut Research Grant.”

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