本文選題：小耳畸形 + 拷貝數(shù)分析��； 參考：《北京協(xié)和醫(yī)學(xué)院》2016年博士論文

【摘要】：研究背景先天性小耳畸形是一種來源于第一二腮弓的發(fā)育異常的先天性出生缺陷,發(fā)病機制比較復(fù)雜。大量研究顯示遺傳因素在小耳畸形發(fā)病中具有重要作用：(1)同卵雙生子共同患病率高于異卵雙生子；(2)家系中患者遺傳癥狀的不完全外顯性；(3)有家族史者占3-34%,遠高于小耳畸形占正常人群的比例；(4)在小耳畸形相關(guān)的綜合征中發(fā)現(xiàn)了基因或染色體異常；(5)誘導(dǎo)特定基因突變可以導(dǎo)致小鼠小耳畸形發(fā)生。由此可見,鑒定小耳畸形遺傳致病位點是明確小耳畸形病因研究的核心。研究目的先天性小耳畸形遺傳學(xué)病因包括染色體水平的變異和基因水平的變異。本研究利用單核苷酸多態(tài)性芯片在全基因組范圍內(nèi)對小耳畸形患者進行拷貝數(shù)變化(CN)分析,篩選可能與先天性小耳畸形有關(guān)的染色體大片段變異,并根據(jù)變異類型對累及的相關(guān)基因進行分析。研究方法采用病例對照方法研究小耳畸形患者進行染色體變異,病例組包括942例小耳畸形患者,對照組為1802例正常人群組。具體方法如下：1.小耳畸形患者染色體大片段變異分析。所有樣本DNA采用Illumina公司的Omni ZhongHua Human基因芯片進行全基因組范圍分型,運用CNV partition進行基因組拷貝數(shù)分析。(1)分析CN的變化：正常二倍體CN=2,拷貝數(shù)增加表示該片段染色體的局部重復(fù),拷貝數(shù)減小的片段代表染色體的局部缺失；(2)結(jié)合CN變化判斷畸變發(fā)生的位置及片段長度；(3)判斷染色體變異類型：分為染色體數(shù)目的變異及染色體結(jié)構(gòu)的變異。2.小耳畸形患者染色體結(jié)構(gòu)變異累及基因分析。(1)染色體片段發(fā)生部分缺失：查找缺失片段內(nèi)功能基因的檢索及定位；(2)染色體片段發(fā)生部分重復(fù)：基因的劑量效應(yīng)和基因的位置效應(yīng)與先天性小耳畸形的潛在關(guān)系。3.小耳畸形相關(guān)的染色體數(shù)目變異及分析。研究結(jié)果1.先天性小耳畸形患者組共發(fā)現(xiàn)染色體大片段變異5例,對照組沒有發(fā)現(xiàn)陽性結(jié)果。對染色體變異在先天性小耳畸形患者和對照組中出現(xiàn)的頻率進行確切概率法檢驗,P=0.0033,表明該差異具有統(tǒng)計學(xué)意義。2.其中2例表現(xiàn)為染色體結(jié)構(gòu)變異：病例一為13號、14號染色體長臂部分重復(fù),14號染色體斷裂片段內(nèi)發(fā)現(xiàn)同源框基因OTX2,OTX2-AS1,對拷貝數(shù)增加的染色體片段進行基因篩選,發(fā)現(xiàn)2個與NCC及耳發(fā)育相關(guān)基因及信號通路基因：BMP4及GSC；病例二為5號染色體長臂部分重復(fù),染色體斷裂片段內(nèi)未發(fā)現(xiàn)小耳畸形相關(guān)的基因,對拷貝數(shù)增加的片段內(nèi)進行檢索,發(fā)現(xiàn)FGF信號通路相關(guān)基因FGF18,FGFR4,FGFl和BMP信號通路相關(guān)基因FST, MSX2,SMAD5。3.另外3例表現(xiàn)為染色體數(shù)目變異：均表現(xiàn)為X染色體增加。其中一例為XXY綜合征；另外兩例為X三體綜合征。研究結(jié)論1.對染色體變異在先天性小耳畸形患者和對照組中出現(xiàn)的頻率進行確切概率法檢驗,顯示先天性小耳畸形患者中出現(xiàn)染色體變異的頻率高于正常對照,說明染色體變異與先天性小耳畸形的發(fā)生存在一定的相關(guān)性。2.14號染色體發(fā)生畸變的位置累及基因OTX2,可能與該病例小耳畸形的發(fā)病有關(guān)。3.13、14號染色體重復(fù)導(dǎo)致GSC、BMP4基因拷貝數(shù)增加,可能與小耳畸形發(fā)生有關(guān)。4.5號染色體長臂部分重復(fù)導(dǎo)致FGF信號通路相關(guān)基因FGF18,FGFR4,FGFl和BMP信號通路相關(guān)基因FST, MSX2,SMAD5拷貝數(shù)增加,可能與小耳畸形發(fā)病有關(guān)。
[Abstract]:Congenital microtia of the background is a congenital birth defect derived from the developmental abnormality of the first branchial arch . The pathogenesis is complicated . A large number of studies show that the genetic factor plays an important role in the pathogenesis of microtia .
( 2 ) incomplete external dominance of the genetic symptoms of the patients in the family department ;
( 3 ) The family history accounts for 3 - 34 % , which is much higher than that of the normal population .
( 4 ) gene or chromosomal abnormality is found in the syndrome associated with the microtia ;
( 1 ) The genetic etiology of congenital microtia was analyzed by using single nucleotide polymorphism ( CN ) .
( 2 ) judging the position of the distortion and the length of the segment according to the change of the CN ;
( 3 ) judging the type of chromosome variation : the variation of the chromosome number and the variation of the chromosome structure ; 2 . the mutation of the chromosome structure of the patient with the small ear malformation is involved in gene analysis ; ( 1 ) the partial deletion of the chromosomal segment : finding and positioning the functional gene in the deletion fragment ;
( 2 ) Partial repeat of the chromosomal segment : The dose effect of the gene and the potential relationship between the position effect of the gene and the congenital microtia . The results showed that there were 5 cases of chromosome aberration and no positive result in the control group .
Case 2 was repeated in the long arm part of chromosome 5 , and no gene related to microtia was found in the fragment of chromosome fragment . It was found that FGF signaling pathway related genes FGF18 , FGFR4 , FGFl and BMP signaling pathway related genes were found to be related to the expression of FGF18 , FGFR4 , FGFl and BMP signaling pathway . The other three cases showed that the number of chromosomes increased . One of them was XXY syndrome .
Conclusion 1 . The frequency of chromosome variation in the patients with congenital microtia and the control group is higher than that of normal controls . It is suggested that the chromosomal variation has a certain correlation with the occurrence of congenital microtia .
【學(xué)位授予單位】：北京協(xié)和醫(yī)學(xué)院
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：R764.7

【參考文獻】

相關(guān)期刊論文 前4條

1 鄒藝輝;;耳的胚胎發(fā)育[J];中華耳科學(xué)雜志;2014年04期

2 吳榮薇;潘博;;小耳畸形的流行病學(xué)和遺傳學(xué)研究進展[J];中華臨床醫(yī)師雜志(電子版);2013年01期

3 杜娟,譚躍球,李麓蕓,盧光t;13q部分三體的分子細胞檢測及其與斜頸體征的可能關(guān)系[J];中華醫(yī)學(xué)遺傳學(xué)雜志;2003年03期

4 譚躍球,李麓蕓,李秀蓉,祁錫玉,盧光t;來源于母親平衡易位的13q14.3→qter三體患兒一例[J];中華兒科雜志;2000年10期

，

本文編號：1900040