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A Case of Partial 5Q Trisomy Associated with Partial 7Q Monosomy

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A Case of Partial 5Q Trisomy Associated with Partial 7Q Monosomy Br J Ophthalmol: first published as 10.1136/bjo.70.8.630 on 1 August 1986. Downloaded from British Journal of Ophthalmology, 1986, 70, 630-633 A case of partial 5q trisomy associated with partial 7q monosomy SATOSHI HARA,' TAKAHIRO YAMADA,' HIROFUMI NAKAI,2 AKIO OHTANI,' AND KATSUYOSHI MIZUNO' From the Departments of 'Ophthalmology, 2Paediatrics, and 'Pathology, Tohoku University School of Medicine, Sendai, Japan SUMMARY A 1-year-old girl with partial 5q trisomy and partial 7q monosomy had ocular abnormalities that included bilateral blepharoptosis and Leber's congenital amaurosis. A single bright-flash electroretinogram (dark-adapted, white stimulation) disclosed subnormal bilateral responses. Her maculas showed a reddish spot surrounded by a broad, greyish retinal zone. Cytogenetic studies disclosed deletion of q22 to the terminal of chromosome 7 and partial trisomy of q31 to the terminal of chromosome 5. Because all reported patients with Sq trisomy have not had Leber's congenital amaurosis, the ocular abnormalities noted in our patient may be explained by the 7q monosomy. copyright. The ability to specify breakpoints and the extent of a deletion have become increasingly reliable with improved techniques that provide elongated chromo- somes with detailed banding.' Twenty-nine cases of partial deletion of 7q224 and 15 cases of distal trisomy http://bjo.bmj.com/ of 5q'3" have been reported with corresponding clinical syndromes. Among these, two patients have had intraocular abnormalities, one with unilateral optic nerve coloboma6 and one with bilateral micro- phthalmos and a large retinal coloboma.23 We describe here a patient with partial trisomy of terminal 5q associated a partial monosomy of on September 26, 2021 by guest. Protected terminal 7q who had ocular abnormalities, including Leber's congenital amaurosis, and non-specific find- ings, such as hypertelorism and blepharoptosis. Case report A 4-month-old girl was referred to us in August 1982 for bilateral blepharoptosis. The product of a normal, full-term pregnancy, the patient, weighed 2128 g at birth. The Apgar score was 2 at one minute, and supplemental oxygen was administered for one hour. The parents were 35 years old, were not con- Correspondence to Satoshi Hara, Department of Ophthalmology, School of Medicine, Tohoku University, Seiryo-cho 1-1, Sendai, Fig. 1 Four-month-oldgirl with telecanthus, broad nose, 980 Miyagi, Japan. and microcephaly. 630 Br J Ophthalmol: first published as 10.1136/bjo.70.8.630 on 1 August 1986. Downloaded from A case of5q trisomy with 7q monosomy 631 Filg. 2A Fig. 28 Fig. 2 A: right eye. B: lefteye. The maculas show a reddish spotsurrounded by a broadgreyish retinal zone. No macular rings areseen. sanguinous, and were in good health. A 3-year-old muscle and only a trace of smooth muscle. The male sibling was normal. blepharoptosis was not corrected despite a maximal Ocular examination of the patient disclosed bi- resection. lateral blepharoptosis and telecanthus (Fig. 1). The On the day of the operation additional ocular copyright. lid fissure was 3 mm wide in the right eye and 2 mm in examinations included electrophysiological studies the left. The levator function was 0 mm in each eye. and fluorescein angiography. The pupillary distance A Tensilon test result was negative. Congenital was 50 mm. The anterior segments appeared normal. anomalies included microcephaly and a broad nose. Ophthalmoscopic examination disclosed no macular Follow-up examination revealed severe mental and rings but showed mottled retina from the posterior to physical retardation associated with spastic palsy and the midperipheral region bilaterally. The maculas hearing impairment. The amino acids in urine and showed a reddish spot surrounded by a broad greyish serum were normal. In November 1983 the patient retinal zone (Figs. 2A, B). Fluorescein angiography http://bjo.bmj.com/ received general anaesthesia to undergo resection of showed granular hyperfluorescence in the regions the levator muscle in the right eye through the that contrasted with the greyish perimacular zones conjunctiva. Resected material contained no skeletal (Fig. 3). A single bright-flash electroretinogram on September 26, 2021 by guest. Protected Fig. 3A Fig. 3B Fig. 3 A: righteye. B: lefteye. Granularhyperfluorescenceisobserved in thegreyishperimacularregionsnoted in Fig. 2. No leakage offluorescein is seen. Br J Ophthalmol: first published as 10.1136/bjo.70.8.630 on 1 August 1986. Downloaded from 632 Satoshi Hara, Takahiro Yamada, Hirofumi Nakai, Akio Ohtani, and Katsuyoshi Mizuno reported. All such cases proved to be inherited from parental insertion or parental translocation, with breakage of the second chromosome at the terminal L -- band. Under these circumstances various cases of partial monosomy associated with partial 5q trisomy may have gone undetected. Our patient may repre- sent the first case of partial 5q trisomy with partial 7q monosomy, although parental translocation could not be proved because the cytogenic data for the father were incomplete. All previously reported patients with partial 5q trisomy had a low birth weight lOOyjVL under 3000 g and physical and mental retardation. Cases of partial trisomy of the distal part of Sq (distal to band 5q31 and to 5q33) commonly had inborn lOms dystrophy and severe to moderate retardation of Fig. 4 Single bright-flash electroretinogram (dark adapted, growth and psychomotor development. Our patient whitestimulation). Both the right (R) and left (L) eyes show also showed this clinical picture and a breakpoint of subnormal responses. 5q31. The ophthalmoscopic appearance of Leber's con- genital amaurosis varies. The most common findings (dark-adapted, white stimulation) disclosed sub- are normal fundus, salt and pepper pigmentary normal responses (Fig. 4). Cytogenic studies were changes, a blond fundus with choroidal atrophy or performed on peripheral blood lymphocytes. Meta- choroideraemia, classic aspect of retinitis pigmen- phase chromosomes derived from synchronised cell tosa, macular changes, or optic atrophy and narrow cultures were treated with trypsin and stained with vessels. Giemsa's stain (Fig. 5). The chromosomes showed The electroretinogram diagnostic for Leber's con- copyright. partial monosomy of the long arm of chromosome 7. genital amaurosis is extinguished or shows only The karyotype was 46, XX, -7, +der(7), t(5:7) minimal response.34 The parents of our case had (q31:q22). A chromosomal study on the mother subnormal responses to the single white flash in dark- showed normal findings. The father was unavailable adapted conditions. Also noted ophthalmoscopically for cytogenic evaluation. were lesions in the posterior pole that included a reddish spot in the macula surrounded by a greyish Discussion retinal zone that showed granular hyperfluorescence http://bjo.bmj.com/ on fluorescein angiography, indicating Leber's Cytogenic analyses have shown a number of cases of congenital amaurosis. chromosomal changes in patients with congenital No intraocular abnormalities have been reported abnormalities. To our knowledge 15 cases of partial trisomy of the long arm of chromosome 5 have been P13 1~~~~2 P 1 3_________3___ on September 26, 2021 by guest. Protected 2 13 22_ - *^ 42 I, 5q 1 ~0 q22 2 I. 3 1 - 3 4 6 0: 2 5 3 36 abnormal chromosome 5 chromosome 7 t'llwchromosomevillvavlll 7I Fig. 5A Fig. 5B Fig. 5 Partialkaryotype ofchromosome 7. A: threepairs ofmetaphase chromosomefrompatient are demonstrated after trypsin-Geimsa banding. Abnormal chromosome with deletion of7q at q22 to the terminal is shown to the right ofeach pair. B: schematicpartial karyotype ofourpatient. Onepair ofchromosome 5 is normal, and onepair chromosome 7is abnormal, having a segment ofq31 to the terminal ofchromosome S instead ofa segment ofq22 to the terminal ofchromosome 7. The karyotype is 46, XX, -7, +der(7), t(5:7) (q31:q22). Br J Ophthalmol: first published as 10.1136/bjo.70.8.630 on 1 August 1986. Downloaded from A case of5q trisomy with 7q monosomy 633 previously in cases of 5q trisomy. The ocular abnor- 15 Franceschini P, Silengo MC, Davi CF, Santoro MA, Prandi G, malities noted in our patient, compared with other Fabris C. Interstitial deletion of the long arm of chromosome 7 46, XX, del (7) (pter-.q 2000): (q 3200-.qter). Hum Genet 1978; patients with 5q trisomy who had an almost identical 44: 345-8. duplicated segment, might be explained by the ad- 16 Koep-De Pater JM, Bijlsma JB, Bleeker-Wagemaker EM, De ditional monosomy. Chromosome 7q deletion syn- France HF, De Vries-Ekkers, CMAM. Two cases with different deletions of the long arm of chromosome 7. J Med Genet 1979; drome has included relatively consistent dysmorphic 16:151-4. findings, including growth deficiency, developmental 17 Valentine H, Sergovich F. A syndrome associated with' inter- delay, bulbous nasal tip, abnormal ears, cleft lip, and stitial deletion ofchromosome 7q. Birth Defects (Original Article genital abnormalities. Acute non-lymphatic leukae- Series XIII 3B) 1977: 261. mia, secondary to occupational or muta- 18 Johnson WE, Kennell JH, McIntyre MM, Van Dyke DL. An therapeutic interstitial deletion of 7q in a female. Am J Hum Genet 1978; 30: genic exposure, has also been frequently associated 84A. with a 7q abnormality.35 Only two reported cases of 19 Stallard R, Jubey RC. Partial monosomy 7q syndrome due to 7q deletion syndrome had, however, associated distal interstitial deletion. Hum Genet 1981; 57: 210-3. ocular abnormalities. These were 20 Gibson J, Ellis PM, Forsyth JS. Interstitial deletion of chromo- microphthalmos some 7. A case report and review of the literature. Clin Genet and retinal coloboma23 and a unilateral optic nerve 1982; 22: 256-65. coloboma,6 though 14 cases of terminal deletion of 21 Bass HN, Crandall BF,'Marcy SM. Two different chromosome the long arm of chromosome 7, terminal to q32 and abnormalities resulting from a translocation carrier father. J terminal to q35, have been reported. Because there Pediatr 1973; 83: 1034-8. 22 Seabright M, Lewis GM. Interstitial deletion of chromosome 7 are no reports of the deletion of chromosome 7q22 to detected in three unrelated patients.
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