本研究收集來自高雄榮總小兒科92個小兒先天性心臟病 (congenital heart disease, CHD) 家族總計95位病人之血液DNA，其中54位病人 (56.8%) 被診斷為心室中隔缺損 (ventricular septal defect, VSD)，所佔比例最高。利用位於第22對染色體上十個涵蓋DiGeorge syndrome 染色體區域 (HSA22q11) 之微衛星型 (microsatellite) 遺傳標記，D22S420、D22S427、D22S1638、D22S941、D22S1648、D22S944、D22S1623、D22S264、D22S303與D22S315，進行台灣小兒先天性心臟病與心臟發育相關基因型的探討。結果顯示，有三十一位心室中隔缺損病人在22q11的位置上有loss of heterozygosity (LOH) 的現象。另外，以生物資訊方法利用Ensembl (EMBL-EBI and the Sanger Institute)，Genome browser (UCSU)，Map viewer (NCBI)，Swiss-Prot database與 FatiGO Data mining with Gene Ontology篩選出位在染色體22q11區域內可能與心臟發育相關的候選基因 TUBA8、CLTCL1、DGCR2、DGCR14、HIRA、TBX1與GNB1L利用定量聚合酵素連鎖反應進行基因劑量之分析。目前結果顯示，微衛星型遺傳標記D22S1648為HSA22q11.2發生LOH頻率較高所在。候選基因TUBA8與HIRA在三十一位心中隔缺損病人中各有48.3%及38.7%單套缺失發生。其中，我們發現有兩位心室中隔缺損與病人在七個候選基因都有單套缺失的情形。此外，在一位房室間管缺損與一位心室中隔缺損病人亦發現在五個候選基因，CLTCL1、DGCR2、DGCR14、HIRA 與 TUBA8有單套缺失。

To identify genes related to the heart developments, a total of 92 CHD families from Kaohsiung Veteran General Hospital, including 290 individuals with 95 affected, were genotyped in this study. Among these CHDs families, 54 were diagnosed as VSDs, accounted for 56.8% of all CHDs. Ten highly polymorphic markers, D22S420, D22S427, D22S1638, D22S941, D22S1648, D22S944, D22S1623, D22S264, D22S303 and D22S315, from centromere to the HSA22q telomere, covering HSA22q11 were genotyped by using a semi-quantitative fluorescent PCR. LOH at loci on 22q11 have been identified in 31 VSDs affected individuals. Candidate genes in HSA22q11 region was identified by bioinformatic methods firstly based on Ensembl (EMBL-EBI and the Sanger Institute), Genome browser (UCSU) and Map viewer (NCBI), and then FatiGO Data mining with Gene Ontology and Swiss-Prot annotations. In order to narrow down more specific cardiac development-related candidate genes within HSA22q11, TUBA8, DGCR2, DGCR14, CLTCL1, HIRA, TBX1 and GNB1L, from the centromere to telomere, were further subjected to dosage analyses by quantitative PCR. Results indicated the most frequent LOH region was localized on D22S1648. There are 48.3% and 38.7% of 31 VSDs patients with one copy deletion in TUBA8 and HIRA, respectively. Two VSDs patients were deleted in all seven candidate genes. Furthermore, there are one CAVC and one VSD patient were deleted in five consecutive genes, TUBA8, DGCR2, DGCR14, CLTCL1 and HIRA.

Chinese abstract -----------------------------------------------------------------Ⅰ
English abstract -----------------------------------------------------------------Ⅱ
Abbreviations --------------------------------------------------------------------Ⅲ
Introduction --------------------------------------------------------- 1
Materials and Methods -------------------------------------------- 3
Results --------------------------------------------------------------- 14
Discussion ----------------------------------------------------------- 23
References ---------------------------------------------------------- 28

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