|
Chromosomal abnormalities and FMR1 gene
premutation in Chinese women with premature menopause
TK Lo, IFM Lo, WK Chan, TMF
Tong, STS Lam
Department of Obstetrics and Gynaecology, Kwong Wah Hospital, 25
Waterloo Road, Hong Kong
OBJECTIVE. To study the prevalence of chromosomal
abnormalities and FMR1 gene premutation in Chinese women
with premature menopause in Hong Kong.
DESIGN. Retrospective study.
SETTING. Clinical Genetic Service, Hong Kong.
PARTICIPANTS. Chinese women with premature menopause
referred for cytogenetic study from January 1983 to November 2003.
MAIN OUTCOME MEASURES. Chromosomal abnormalities,
FMR1 gene premutation.
RESULTS. Chromosomal abnormalities were present
in 15.6% of Chinese women who suffered premature menopause. X-chromosome
abnormality was involved in over 80% of cases. FMR1 gene
premutation was present in 0.86% of 116 cases screened for this
abnormality. The predominance of X-chromosome abnormality accounted
for the shorter stature, younger menopausal age, and higher prevalence
of dysmorphic features among the cytogenetically abnormal patients.
However, on logistic regression, no clinical feature was significantly
correlated with cytogenetic abnormality.
CONCLUSIONS. The prevalence of chromosomal abnormalities
among Hong Kong Chinese women who suffer premature menopause was
comparable with that of Caucasian and Chinese populations elsewhere.
Because clinical features are poor predictors of cytogenetic abnormality,
a pragmatic approach to screening is advocated. The carrier rate
of fragile X premutation in these women appeared lower than that
of Caucasians. Nevertheless, a search for FMR1 gene premutation,
in addition to conventional chromosomal study, has important implication
for prenatal diagnosis and fertility management for the extended
family.
Hong Kong Med J 2005;11:243-50
Key words: Fragile X syndrome; Menopause, premature;
Ovarian failure, premature; X chromosome
|
