Clinical and genetic analysis for four Chinese families with Prader-Willi syndrome.
Prader-Willi syndrome (PWS) is a complex, genetic, multisystem disorder. Its major clinical features include neonatal hypotonia and failure to thrive, mental retardation, hypogonadism, short hands and feet, hyperphagia-caused obesity, and characteristic appearance. The genetic basis of PWS is also complex. It is caused by the absence of expression of the active paternal genes such as the SNRPN, NDN, and possibly others in the PWS critical region on 15q11-13. PWS is in effect a contiguous gene syndrome resulting from deletion of the paternal copies of the imprinted. Consensus in clinical diagnostic criteria was established in 1993. However, identifying relevant patients for tests remains a challenge for most practitioners, as many features of the disorder are nonspecific, and others can be subtle or evolved over time. Consequently, molecular genetic tests can be used to diagnose PWS accurately, allowing early diagnosis of the syndrome. High resolution G-banding, high resolution cytogenetic methylation-specific PCR (MS-PCR), and fluorescence in situ hybridization (FISH) are routinely used to diagnose PWS. In this study, four Chinese patients, with typical PWS features, were detected by MS-PCR and FISH. Three were cytogenetically normal, but lacked paternal expression of proximal chromosome 15q because of maternal uniparental disomy (UPD). The other one, however, demonstrated an unbalanced de novo translocation 46, XX, t (7; 15).
Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, 200025, People's Republic of China.
Yu-wen
YW
Zhang
Hui-ying
HY
Jia
Jie
J
Hong
Yan
Y
Ge
Hui-jie
HJ
Zhang
Chun-fang
CF
Shen
Lei
L
Ye
Bin
B
Cui
Xiao-ying
XY
Li
Wei-qiong
WQ
Gu
Yi-fei
YF
Zhang
Wei-qing
WQ
Wang
Guang
G
Ning
D000293:Adolescent; D044466:Asian People / Q000235:genetics*; D002648:Child; D002884:Chromosomes, Human, Pair 15; D019175:DNA Methylation; D005192:Family Health; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D009767:Obesity, Morbid / Q000235:genetics / Q000473:pathology; D016133:Polymerase Chain Reaction; D011218:Prader-Willi Syndrome / Q000235:genetics* / Q000473:pathology; D014178:Translocation, Genetic; D055815:Young Adult