Identification of Melanoma Susceptibility Gene at 1p22

1p22 黑色素瘤易感基因的鉴定

• 批准号: 7074757
• 负责人: JEFFREY M. TRENT
• 金额: $ 54.88万
• 依托单位: TRANSLATIONAL GENOMICS RESEARCH INST
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-27 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7074757
• 关键词: alleles; bioinformatics; cancer risk; cell line; clinical research; comparative genomic hybridization; experimental designs; family genetics; gene expression; gene mutation; genetic screening; genetic susceptibility; genotype; high throughput technology; human subject; lymphocyte; melanocyte; melanoma; microarray technology; neoplasm /cancer genetics; nucleic acid sequence; single nucleotide polymorphism

DESCRIPTION (provided by applicant): Despite decades of research, metastatic cutaneous malignant melanoma (CMM) remains an incurable disease, demonstrating a median survival time of 9 months, with a 5-year survival rate of less than 5 percent. Further, over the past 20 years, the incidence of CMM has increased dramatically worldwide. Critical to this study, a positive family history of the disease is among the most established risk factors for CMM; 10% of CMM cases result from an inherited predisposition. Although mutations in two genes, CDKN2A and CDK4, confer an increased risk of CMM, they account for only 20% - 25% of families with multiple cases of CMM. We hypothesize that that there are additional CMM-predisposition genes, and this application provides an empirically based, technologically innovative approach to identify one such gene. We have performed a genome-wide linkage scan of 82 CMM kindreds with no involvement of CDKN2A or CDK4, and have identified a novel CMM susceptibility locus on chromosome 1 (1p22). To identify the melanoma susceptibility gene at this locus (Aim 1), we are integrating multiple experimental methods aimed at prioritizing candidate genes for mutation screening. Specifically, we will: (a) perform high-resolution SNP-typing and look for evidence of haplotype sharing between CMM families in order to further narrow the critical region; (b) design a custom oligonucleotide microarray representing all potential coding sequences within the 1p22 critical region in order to identify novel genes and to characterize tissue-specific gene expression for the purpose of candidate gene prioritization; and (c) design a custom 1p22 oligonucleotide microarray for comparative genomic hybridization (CGH) and look for partial- or whole-gene deletions in DNA from patient lymphocytes as well as melanoma cell lines with hemizygous loss at 1p22. Based on these data, we will prioritize our gene candidates and (d) screen genes for mutations using DNA sequencing. Following the identification of the 1p22 melanoma susceptibility gene, we will determine the prevalence of 1p22 gene mutation/loss (Aim 2) in a panel of melanoma cell lines, tumors, and nevi, and propose an experimental approach to understand its mechanism of action. Lastly, we will test the hypothesis that Iow-penetrance susceptibility alleles of the melanocortin receptor (MCIR) modify the penetrance of 1p22 susceptibility gene mutations (Aim 3) and genotype both affected and unaffected members of our 1p22-mutation positive families for these alleles.

描述(申请人提供)：尽管经过几十年的研究，转移性皮肤恶性黑色素瘤(CMM)仍然是一种无法治愈的疾病，中位生存期为9个月，5年生存率不到5%。此外，在过去的20年里，CMM的发病率在全球范围内急剧增加。对这项研究至关重要的是，阳性家族史是CMM最确定的危险因素之一；10%的CMM病例是由遗传易感性引起的。虽然CDKN2A和CDK4这两个基因的突变增加了CMM的风险，但在有多个CMM病例的家庭中，它们只占20%-25%。我们假设还有更多的CMM易感基因，这项应用提供了一种基于经验的、技术创新的方法来识别一个这样的基因。我们对82个没有CDKN2A或CDK4参与的CMM家系进行了全基因组连锁扫描，并在1号染色体(1p22)上发现了一个新的CMM易感基因。为了识别该基因座的黑色素瘤易感基因(目标1)，我们正在整合多种实验方法，旨在优先筛选突变筛选的候选基因。具体地说，我们将：(A)进行高分辨率的SNP分型，并寻找CMM家族之间共享单倍型的证据，以进一步缩小关键区域；(B)设计定制的寡核苷酸微阵列，代表1p22关键区域内的所有潜在编码序列，以便识别新基因和表征组织特异性基因表达，以便确定候选基因的优先顺序；以及(C)设计定制的1p22寡核苷酸微阵列，用于比较基因组杂交(CGH)，并寻找患者淋巴细胞以及1p22半合子缺失的黑色素瘤细胞系DNA中的部分或全部基因缺失。基于这些数据，我们将优先选择我们的候选基因，并(D)使用DNA测序筛选基因突变。在确定1p22黑色素瘤易感基因后，我们将确定1p22基因突变/缺失(AIM 2)在一组黑色素瘤细胞系、肿瘤和痣中的流行率，并提出一种实验方法来了解其作用机制。最后，我们将检验这一假设，即黑素皮质素受体(MCIR)的低外显性易感等位基因改变了1p22易感基因突变的外显率(AIM 3)，并对1p22突变阳性家族中受影响和未受影响的成员进行了这些等位基因的基因分型。