MOLECULAR GENETIC ANALYSIS OF THE PRADER-WILLI SYNDROME LOCUS

普拉德-威利综合征（PWS）是一种以精神疾病为特征的遗传性疾病 发育迟缓、肥胖和性腺功能减退。 大多数患者显示 染色体15 q11 q13的特征性缺失。 这种删除是 总是父亲的血统。 在没有可检测到的 缺失，观察到染色体15 q的单亲母体二体性。 这些发现表明PWS疾病位点在遗传上是 印记 我们建议把工务计划的重要范围界定得更窄 通过鉴定和克隆断裂点连接， 与PWS相关的不平衡易位 Cosmid和lambda 从流式分选的染色体15 q11 q13材料构建的噬菌体文库 以及酵母人工染色体克隆将被用来克隆 断点连接 这些试剂也将用于构建 PWS关键区域的重叠群。 转录因子中的潜在转录单位 然后将识别PWS关键区域。 我们将决定 映射到PWS关键区域的任何转录序列 显示等位基因特异性表达。 这将通过使用 基于PCR的3'端短串联重复序列检测 来自PWS关键区的cDNA的非翻译区。 的基因 从PWS临界区，这是专门表示从 父本染色体15将被分类为PWS的候选基因。

Prader-Willi syndrome (PWS) is a genetic disease characterized by mental retardation, obesity and hypogonadism. The majority of patients display a characteristic deletion of chromosome 15q11q13. This deletion is always of paternal origin. In cases where there is no detectable deletion, uniparental maternal disomy of chromosome 15q is observed. These findings indicate that the PWS disease locus is genetically imprinted. We propose to more narrowly delineate the PWS critical region of deletion overlap by identifying and cloning the breakpoint junction of an unbalanced translocation associated with PWS. Cosmid and lambda phage libraries constructed from flow sorted chromosome 15q11q13 material as well as yeast artificial chromosome clones will be used to clone the breakpoint junction. These reagents will also be used to construct a contig of the PWS critical region. Potential transcription units in the PWS critical region will then be identified. We will determine whether any of the transcribed sequences which map to the PWS critical region display allele-specific expression. This will be accomplished using a PCR-based assay for short tandem repeats which occur in the 3' untranslated regions of the cDNAs from the PWS critical region. A gene from the PWS critical region which is expressed exclusively from the paternal chromosome 15 will be classified as a candidate gene for PWS.