Ryynänen M, Heinonen S, Makkonen M, Kajanoja E, Mannermaa A, Pertti K
Department of Obstetrics and Gynaecology, Kuopio University Hospital, Finland.
Eur J Hum Genet. 1999 Feb-Mar;7(2):212-6. doi: 10.1038/sj.ejhg.5200285.
Fragile X syndrome is the second leading cause of mental retardation after Down syndrome. Most women carriers of the fragile X mutation are unaware of their condition. We critically evaluated whether screening pregnant women at low risk for FMR1 mutation would be feasible as a routine part of antenatal care in general practice. We also studied acceptance and attitudes to gene testing. From July 1995 until December 1996, a carrier test was offered at the Kuopio City Health Centre free of charge to all pregnant women in the first trimester following counselling given by midwives on fragile X syndrome. All women found to be carriers of FMR1 gene mutations underwent detailed genetic counselling and were offered prenatal testing. Attitudes towards the gene test were elicited by questionnaire. Most pregnant women (85%) elected to undertake the gene test. Six women were found to be carriers (a rate of 1 in 246), and all subsequently accepted prenatal testing. Three foetuses had a normal FMR1 gene, one had a large premutation, one a 'size mosaic' mutation pattern, and another a full mutation. This observational and interventional study demonstrates that antenatal screening provides an effective way of identifying carriers and incorporating prenatal testing into this process.
脆性X综合征是仅次于唐氏综合征的第二大智力发育迟缓病因。大多数脆性X突变携带者女性并不知道自己的状况。我们严格评估了对FMR1突变低风险孕妇进行筛查作为全科医疗中常规产前检查一部分是否可行。我们还研究了对基因检测的接受度和态度。从1995年7月至1996年12月，在库奥皮奥市健康中心，在助产士就脆性X综合征进行咨询后，为所有孕早期孕妇免费提供携带者检测。所有被发现为FMR1基因突变携带者的女性都接受了详细的遗传咨询，并被提供了产前检测。通过问卷调查了解对基因检测的态度。大多数孕妇（85%）选择进行基因检测。发现6名女性为携带者（比例为1/246），随后她们都接受了产前检测。3名胎儿FMR1基因正常，1名有大的前突变，1名有“大小嵌合”突变模式，另1名有完全突变。这项观察性和干预性研究表明，产前筛查是识别携带者并将产前检测纳入该过程的有效方法。
