Letters to the Editor SHOX Point Mutations in Dyschondrosteosis
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J Med Genet 2001;38:323–351 323 Letters to the Editor J Med Genet: first published as 10.1136/jmg.38.5.323 on 1 May 2001. Downloaded from SHOX point mutations in dyschondrosteosis Céline Huber, Veronica Cusin, Martine Le Merrer, Michèle Mathieu, Véronique Sulmont, Nathalie Dagoneau, Arnold Munnich, Valérie Cormier-Daire Dyschondrosteosis (DCS) has been recently Table 2 SHOX point mutations identified in DCS patients ascribed to mutations of the SHOX gene on the pseudoautosomal region of the X and Y chro- Sequence change Exon Protein eVect mosomes.12 Most cases are accounted for by Family 4 106–107 del CG 2 77X large scale deletions3–7 and only two point Family 5 334 C→T 3 Q112X Family 6 445 G→T 3 E149X mutations have been hitherto identified in exon Family 7 481 ins GT 3 181X 4 (R195 X and Y199X12). Here, we show that Family 8 517 C→T 4 R173C point mutations in various regions of the 1 SHOX gene also play an important role in the one nonsense mutation ). Studying eight addi- pathogenesis of the disease. tional DCS families, we describe here three A total of 22 aVected subjects belonging to deletions and five point mutations of SHOX. Taken together, these data suggest that SHOX eight families were included in the study. deletion is the most frequent common disease Inclusion criteria for aVected status were short causing mechanism in DCS (10/16, 62.5%) stature (2 SD below normal) with short and that point mutations also account for a sig- forelimbs and distal radioulnar deformity on nificant fraction of our patients (6/16, 37.5%). forearm x rays. This study also supports the view that hap- The 22 patients and their relatives were loinsuYciency is the most frequent mech- genotyped using microsatellite DNA markers anism in DCS (10 deletions and five nonsense of the pseudoautosomal region (CA-SHOX, and frameshift mutations in 15/16 families). DXYS233, DXYS234, DXYS228). Linkage Among the five novel mutations reported here, J Med Genet studies supported the mapping of the disease only one was a missense mutation resulting in 2001;38:323 gene to Xp22.3 in all families and hemizygos- an amino acid change in the homeodomain of ity at the CA-SHOX locus was observed in SHOX. Interestingly, this family was not clini- Department of cally diVerent from the others. Indeed, all Genetics and INSERM three families (families 1-3, data not shown). http://jmg.bmj.com/ U393, Hôpital Necker In families 4-8, PCR amplification and patients had short stature and x ray deformity Enfants Malades, 149 sequence analysis of the five translated exons of of the forearms although intrafamilial variabil- rue de Sèvres, 75743 the SHOX gene (table 1) led to the detection of ity was consistently observed with males being Paris Cedex 15, France five diVerent mutations which consistently usually less severely aVected. C Huber cosegregated with the disease (table 2). In fam- In conclusion, this study shows that point V Cusin mutations of the SHOX gene account for a sig- M Le Merrer ily 4, a two base pair deletion in exon 2 led to a N Dagoneau frameshift and a translation termination at nificant number of DCS patients and shows A Munnich codon 77. In families 5 and 6, base changes at that haploinsuYciency is the most frequent on September 26, 2021 by guest. Protected copyright. V Cormier-Daire nucleotides 334 and 445 respectively created a disease causing mechanism in DCS. stop codon in exon 3 (Q112X and E149X). In Service de Génétique, family 7, a GT insertion at codon 161 led to a 1 Belin V, Cusin V, Viot G, Girlich D, Toutain A, Moncla A, Amiens, France Vekemans M, Le Merrer M, Munnich A, Cormier-Daire V. M Mathieu premature stop codon. All four mutations SHOX mutations in dyschondrosteosis (Leri-Weill syn- resulted in a premature translation termination. drome). Nat Genet 1998;19:67-9. → 2 Shears DJ, Vassal HJ, Goodman FR, Palmer RW, Reardon Department of Finally, in family 8, a C T transition in exon 4 W, Superti-Furga A, Scambler PJ, Winter RM. Mutation Pediatrics, American changed an arginine into a cysteine in the and deletion of the pseudoautosomal gene SHOX cause Leri-Weill dyschondrosteosis. Nat Genet 1998;19:70-3. Memorial Hospital, protein (R173C). This mutation was found in 3 Kosho T, Muroya K, Nagai T, Fujimoto M, Yokoya S, Reims, France the aVected mother and her three aVected chil- Sakamoto H, Hirano T, Terasaki H, Ohashi H, Nishimura V Sulmont G, Sato S, Matsuo N, Ogata T.Skeletal features and growth dren but neither in the healthy father nor in 90 patterns in 14 patients with haploinsuYciency of SHOX: control chromosomes. implications for the development of Turner syndrome. J Correspondence to: Clin Endocrinol Metab 1999;84:4613-21. Dr Cormier-Daire, We have reported on SHOX deletions and a 4 Calabrese G, Fischetto R, Stuppia L, Capodiferro F, [email protected] nonsense mutation in DCS (seven deletions, Mingarelli R, Causio F, Rocchi M, Rappold GA, Palka G. X/Y translocation in a family with Leri-Weill dyschon- Table 1 Detailed PCR conditions for SHOX exon amplification. The exon numbers have drosteosis. Hum Genet 1999;105:367-8. been assigned according to Blaschke and Rappold8 5 Stuppia L, Calabrese G, Borrelli P, Gatta V, Morizio E, Mingarelli R, Di Gilio MC, Crino A, Giannotti A, Rappold GA, Palka G. Loss of the SHOX gene associated with Leri- Annealing Product size Weill dyschondrosteosis in a 45,X male. J Med Genet 1999; Primer sequence temperature (°C) (bp) 36:711-13. 6 Spranger S, Schiller S, Jauch A, WolV K, Rauterberg-Ruland Exon 2 5' GAGACGCGCGCATCCACCA 64 I, Hager D, Tariverdian G, Troger J, Rappold G. Leri-Weill Exon 2 3' GAGGCGCCGAACCCCAGGAG 64 382 syndrome as part of a contiguous gene syndrome at Exon 3 5' AAAACCTCCCCGGCCTCAG 64 Xp22.3. Am J Med Genet 1999;83:367-71. Exon 3 3' GTGGCTGTACGCGTGCGCTGTG 64 332 7 Schiller S, Spranger S, Scheshinger B, Fukami M, Merker S, Exons 4–5 5' GGGAGGCTGGGCTGGGTTC 64 Drop S, Tröger J, Knoblauch H, Kunze J, Seidel J, Rappold Exons 4–5 3' GGGGAAGGGAGCAGCCAGGAA 64 378 GA. Phenotypic variation and genetic heterogeneity in Leri-Weill syndrome. Eur J Hum Genet 2000;8:54-62. Exon 6a 5' TTCACCATGTTAGCCAGGAA 64 8 Blaschke RJ, Rappold GA. SHOX: growth, Léri-Weill and Exon 6a 3' ATCACCTGAGGTCAGGAGTT 64 376 Turner syndromes. Trends Endocrinol Metab 2000;6:227-30. www.jmedgenet.com 324 Letters Phenotypic heterogeneity of CYP1B1: mutations J Med Genet: first published as 10.1136/jmg.38.5.323 on 1 May 2001. Downloaded from in a patient with Peters’ anomaly Andrea Vincent, Gail Billingsley, Megan Priston, Donna Williams-Lyn, Joanne Sutherland, Tom Glaser, Edward Oliver, Michael A Walter, Godfrey Heathcote, Alex Levin, Elise Héon Congenital glaucoma refers to a genetically entirely well with no other malformations and J Med Genet heterogeneous group of distinctive clinical dis- no significant family history. 2001;38:324–326 eases characterised by increased intraocular A diagnosis of congenital glaucoma and pressure most often associated with increased Peters’ anomaly with no significant family his- Department of corneal diameter, corneal oedema, and conse- tory was made. Bilateral trabeculotomies were Ophthalmology, The quent visual impairment. Primary congenital performed to decrease the IOP followed by a Hospital for Sick Children, Toronto, glaucoma (PCG) is associated with a primary left corneal transplant for visual rehabilitation. Ontario, Canada angle defect, whereas secondary congenital At surgery, the undersurface of the cornea A Vincent glaucoma is associated with a more generalised showed a central, Y shaped, posteriorly project- J Sutherland developmental anomaly of the anterior seg- ing opacity that corresponded to a raised opac- A Levin ment such as seen in Peters’ anomaly. The ity on the anterior capsule of the lens. This E Héon inheritance of PCG is usually autosomal reces- overlapped the position of the fetal sutures and The Research sive. suggested the existence of previous keratolen- Institute, The Hospital Peters’ anomaly consists of corneal opacity, ticular adhesions during development. The for Sick Children, defects in the posterior structures of the lens also showed a pulverulent (powdery) cata- University of Toronto, cornea, and iridocorneal and/or keratolenticu- ract through which there was a good red reflex. Toronto, Ontario, lar adhesions, and it most frequently occurs Subsequently, the IOPs were diYcult to Canada sporadically.1 Over 50% of subjects develop A Vincent control in both eyes, requiring frequent surgery G Billingsley glaucoma in childhood. Numerous aetiologies and medication. At the most recent examina- A Levin have been proposed including chromosomal tion at 6 years of age, his right eye showed signs E Héon abnormalities, teratogens,1 and mutations in of advanced but controlled glaucoma with a the eye developmental genes PAX62–4 and cup:disc ratio of 0.8 to 0.9 OD. His left eye The Vision Science PITX2.5 However, large subsets of Peters’ became phthisical (shrunken). Research Program, anomaly cases are without molecular charac- Microscopic examination of the left corneal University Health Network, Toronto terisation. button removed at transplantation showed that Western Hospital, Primary congenital glaucoma has been the corneal epithelium was of normal thick- Toronto, Ontario, linked to chromosomes 1p36 (GLC3B) and ness, although there was some oedema of the http://jmg.bmj.com/ Canada 2p21 (GLC3A), but only the GLC3A gene has basal cells (fig 1, below). Bowman’s membrane A Vincent been identified. This gene, CYP1B1, encodes a was not recognisable and the anterior stroma G Billingsley broadly expressed cytochrome P450 enzyme M Priston was hypercellular with a disordered lamellar D Williams-Lyn (P4501B1) whose natural substrate is un- pattern.