González Sara, Blanco Ignacio, Campos Olga, Julià María, Reyes José, Llompart Alfred, Cabeza Elena, Germà Josep Ramon, Obrador Antoni, Capellá Gabriel
Laboratori de Recerca Translacional, IDIBELL-Institut Català d'Oncologia, Av. Gran Vía Km 2.7 L'Hospitalet, 08907 Barcelona, Spain.
Cancer Genet Cytogenet. 2005 Apr 1;158(1):70-4. doi: 10.1016/j.cancergencyto.2004.07.003.
The incidence of familial adenomatous polyposis (FAP) is approximately 7.4 per 100,000 inhabitants. APC gene mutations have been found in 60-70% of all FAP families, codons 1309 (20%) and 1061 (8%) being known hot-spots. We searched for mutations in the APC gene in a population-based registry of FAP from the Spanish Balearic Islands. Fifty-one members of 12 FAP families registered in the Balearic Islands Cancer Registry were studied; three of them were de novo cases. Mutations in the APC gene were analyzed by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and sequencing. Haplotype was established by combining intra- and extragenic markers. Mutations in the APC gene were detected in 10 out of 12 (83%) families analyzed. Six families shared the same mutation, a 5-bp deletion at codon 1061 (c.3221_3225delACAAA). Five of the families containing this mutation shared the same haplotype and originated in the same geographic area. The codon 1061 mutation in the APC gene is the most common one in the Balearic Islands. Although this codon is a hot-spot, the haplotype analysis of these families is consistent for the presence of a founder effect of the 5-bp deletion at codon 1061 in FAP families in the Spanish Balearic Islands.
家族性腺瘤性息肉病（FAP）的发病率约为每10万居民中有7.4例。在所有FAP家族中，60%-70%发现有APC基因突变，已知密码子1309（20%）和1061（8%）为热点突变位点。我们在西班牙巴利阿里群岛一个基于人群的FAP登记处中搜索APC基因的突变情况。研究了在巴利阿里群岛癌症登记处登记的12个FAP家族中的51名成员；其中3例为新发病例。通过聚合酶链反应-单链构象多态性（PCR-SSCP）和测序分析APC基因的突变。通过组合基因内和基因外标记来确定单倍型。在分析的12个家族中的10个（83%）检测到了APC基因的突变。6个家族具有相同的突变，即密码子1061处的5碱基缺失（c.3221_3225delACAAA）。包含该突变的5个家族具有相同的单倍型，且起源于同一地理区域。APC基因密码子1061突变是巴利阿里群岛最常见的突变。尽管该密码子是一个热点突变位点，但对这些家族的单倍型分析表明，西班牙巴利阿里群岛FAP家族中密码子1061处5碱基缺失存在奠基者效应。
