先天性巨结肠患者人类巨细胞病毒UL144基因多态性的研究

目的研究人类巨细胞病毒（human cytomegalovirus,HCMV）UL144基因在先天性巨结肠（Hirschsprung＇s disease,HD）临床株中的多态性,探讨HCMV UL144基因多态性与致病性之间的关系.方法随机选取53个先天性巨结肠患儿痉挛段结肠手术标本及经荧光定量PCR方法检测HCMV DNA为阳性的4个HD患儿的尿标本,对照组为无症状或仅有皮肤轻度黄疸的6个尿标本.应用巢式聚合酶链反应的方法,扩增HCMV UL144基因开放阅读框架（ORF）,扩增阳性的临床株进行双向DNA测序,最后通过DNAclub、Bioedit、DNAstar、GeneDoc等软件进行分析.结果23份HD痉挛段肠组织（46%）及4份尿标本HCMV UL144基因扩增阳性,并且完成测序.种系进化树分析结果显示25个HD患儿的DNA序列分为3个基因型,G1A型64.0%,G2型24%,G3型12%.与对照组比较,经χ^2检验,χ^2=10.93,P为0.012;其中HD临床株G1A和G3型基因经Fisher检验,P为0.015,差异具有统计学意义.全结肠型、长段型及普通型HD分散分布于UL144各个基因型中.结论HD与HCMV感染有关,HCMV可能是HD的病因之一;在HD患儿中,HCMV感染以UL144基因G1A型为主;HD的临床分型与HCMV UL144基因分型无关.

Polymorphisms of human cytomegalovirus UL144 open reading frame in Hirschsprung's disease

Human cytomegalovirus (HCMV) is infection one of the most common causes of congenital malformations. Hirschsprung's disease (HD) is a common malformation in infants. In this study, the UL144 gene polymorphism of HCMV was analysed to explore the relationship between polymorphisms of HCMV UL144 ORF and HD. Methods We amplified 53 specimens of bowel in aganglionic segment and 4 urine samples of HD by nest PCR method. The control group was urine samples of cases with mild or asymptomatic HCMV infected infants. The amplicons were sequenced in both strains. UL144 ORF was analyzed. Results Twenty-seven of 57 (47.4%) clinical strains were successfully amplified and sequenced. The UL144 sequences distributed among three genotypes (Group 1A, 2, and 3), but not in GrouplB and Group 1C. The major genotype of UL144 was Group 1A (64% ) , while Group 3 amounted only to 12% . In control group, Group 1A was not detected, while the three major genotypes were Group 1B (16.7% ) , Group 2 (50% ) , and Group 3 (33% ) respectively. The predominant genotype was Group 1A. On clinical manifestation, UL144 sequences from the ordinary, entire colon, and longer segment sporadically distributed in UL144 genotypes. Conclusion Congenital HCMV infection may be etiologically associated with HD in some infants. The UL144 genetic types were related to HD and HCMV in UL144 Group 1A with potential trophism to intestinal never tissue. No correlation was found between UL144 genotype and clinical phenotype of HD.