Rejeb Imen, Ben Jemaa Lamia, Chaabouni Habiba
Laboratoire de Génétique Humaine, Faculté de Médecine de Tunis, Tunisie.
Tunis Med. 2009 May;87(5):311-8.
Mental retardation (MR) is a group of heterogeneous clinical conditions. There are more than 900 genetic disorders associated with MR and it affects around 3% of the general population. Many MR conditions described are syndromic, fragile X syndrome being the most common clinical entity among them. X linked mental retardation (XLMR) is subdivided in two categories: syndromic XLMR (MRXS) when MR is associated with clinical features and non-syndromic XLMR (MRX) when MR is isolated.
The aim of this systematic review of the literature was to join together the results of several studies related to X linked mental retardation and to present various genes implicated in this disease. In this review, focus has been given on genes implicated in mental retardation, the clinical data and on phenotype-genotype correlations.
An exhaustive electronic and library research of the recent literature was carried out on the Web sites "Science Direct" and "Interscience Wiley". The key words used were "mental retardation", "X chromosome", "gene", "syndromic mental retardation", "non-syndromic mental retardation".
In this review a number of X linked genes, the clinical features associated with the gene abnormality, and the prevalence of the disease gene are discussed. We classified these genes by order of their first implication in MR. A table presented on the XLMR Update Web site who list the 82 known XLMR genes is available as XLMR Genes and corresponding proteins.
智力迟钝（MR）是一组异质性临床病症。有900多种与智力迟钝相关的遗传疾病，它影响着约3%的普通人群。所描述的许多智力迟钝病症是综合征性的，脆性X综合征是其中最常见的临床类型。X连锁智力迟钝（XLMR）可分为两类：当智力迟钝与临床特征相关时为综合征性XLMR（MRXS），当智力迟钝单独出现时为非综合征性XLMR（MRX）。
本系统文献综述的目的是汇总几项与X连锁智力迟钝相关的研究结果，并介绍涉及该疾病的各种基因。在本综述中，重点关注了与智力迟钝相关的基因、临床数据以及表型-基因型相关性。
在“Science Direct”和“Interscience Wiley”网站上对近期文献进行了详尽的电子和图书馆检索。使用的关键词为“智力迟钝”“X染色体”“基因”“综合征性智力迟钝”“非综合征性智力迟钝”。
在本综述中，讨论了一些X连锁基因、与基因异常相关的临床特征以及疾病基因的患病率。我们根据这些基因首次与智力迟钝关联的顺序对它们进行了分类。XLMR Update网站上有一个列出82个已知XLMR基因的表格，可作为XLMR基因及相应蛋白质获取。
