Visich A A, Barreiro C Z, Chertkoff L P
Laboratorio de Biología Molecular, Servicio de Genética, Hospital de Pediatría Juan P. Garrahan, Buenos Aires, Argentina.
Medicina (B Aires). 2001;61(1):23-7.
Argentine population is highly heterogeneous for the cystic fibrosis (CF) transmembrane regulator (CFTR) gene mutations. The study of 14 more common mutations identified both mutated alleles in only 51% of patients. This study confirmed the diagnosis of cystic fibrosis in these patients and enabled the detection of asymptomatic carriers in their families. However, in the remaining patients the direct molecular assay did not provide the necessary information for genetic counselling. To establish the mutated allele transmission in the affected families, negative for the most common mutations, three microsatellites (IVS17bTA, IVS8CA and IVS17bCA) located in intronic regions of CFTR gene were studied. In the 40 CF families analyzed, different allelic variants were detected: 15 for IVS17bTA, 10 for IVS8CA and 4 for IVS17bCA. Polymorphism information content and heterozygosity were high, except for IVS17bCA. By the simultaneous analysis of the three microsatellites we could counsel 100% of the families. Ours results show that these microsatellites are an excellent group of markers for linkage studies in cystic fibrosis families of the Argentine population.
阿根廷人群中囊性纤维化(CF)跨膜调节因子(CFTR)基因突变具有高度异质性。对14种较常见突变的研究发现,仅51%的患者中检测到两个突变等位基因。该研究证实了这些患者的囊性纤维化诊断,并能够在其家族中检测出无症状携带者。然而,在其余患者中,直接分子检测未能为遗传咨询提供必要信息。为了确定受影响家族中最常见突变呈阴性的突变等位基因传递情况,对位于CFTR基因内含子区域的三个微卫星(IVS17bTA、IVS8CA和IVS17bCA)进行了研究。在分析的40个CF家族中,检测到不同的等位基因变体:IVS17bTA有15种,IVS8CA有10种,IVS17bCA有4种。除IVS17bCA外,多态性信息含量和杂合度都很高。通过同时分析这三个微卫星,我们能够为100%的家族提供遗传咨询。我们的结果表明,这些微卫星是阿根廷人群囊性纤维化家族连锁研究的一组优秀标记。