MONOZYGOTIC TWINS DISCORDANT FOR THE RUSSELL-SILVER SYNDROME

Citation
W. Bailey et al., MONOZYGOTIC TWINS DISCORDANT FOR THE RUSSELL-SILVER SYNDROME, American journal of medical genetics, 58(2), 1995, pp. 101-105
Citations number
25
Categorie Soggetti
Genetics & Heredity
ISSN journal
01487299
Volume
58
Issue
2
Year of publication
1995
Pages
101 - 105
Database
ISI
SICI code
0148-7299(1995)58:2<101:MTDFTR>2.0.ZU;2-Q
Abstract
Russell-Silver syndrome (RSS) is a pattern of malformation characteriz ed by intrauterine and postnatal growth retardation, limb asymmetry, t riangular face, and hypospadias. We report on a patient, from a triple t pregnancy, who was one of identical male twins discordant for RSS. R .B. was a 710-g male born at 33 weeks of gestation, with hypospadias, chordee, and undescended testes. He had a normal 46,XY karyotype and n o renal abnormalities. Female triplet A weighed 1,843 g, and male trip let B weighed 1,920 g. Both had normal physical findings and neonatal period. R.B. was first seen by us at age 6 7/12 years with short statu re, triangular and asymmetric face, lower limb length discrepancy, and surgically repaired genital anomalies. Growth hormone testing results were normal. At age 8 7/12 years the brothers appeared physically ide ntical ex cept for size, with a height differential of 114.25 vs. 121. 5 cm. Testing to establish biological zygosity was performed using VNT R (variable number tandem repeat) DNA probes YNH24 (D2S44), CMM101 (D1 4S13), EFD52 (D17S26), TBQ7 (D10S28), and 3'HVR (D16S85), PCR loci MCT 118 (D1S80), and HLA-DQ alpha. These data indicate a >99.99% probabili ty of triplets B and C being monozygotic twins. While most occurrences of RSS are sporadic, familial cases suggesting autosomal dominance ha ve been reported. Three other cases of probable monozygotic twins with RSS have been described. The significance of this confirmation of dis cordance in determining the cause of RSS is discussed. (C) 1995 Wiley- Liss, Inc.