CAJ | 학술논문

目的对中国一常染色体显性遗传先天性前极白内障家系进行致病基因的定位与候选基因突变检测.方法采集家系成员外周静脉血,提取基因组DNA.选用ABI公司提供的约400个遗传标记物进行基因扫描.基因扫描分初步扫描和精细扫描两步进行.首先对已报道的先天性白内障候选区域进行初步扫描,之后在阳性区域内进行精细扫描.数据经连锁分析,初步确定致病基因所在染色体区域.在阳性区域内选取更高密度的荧光标记物进行精细扫描,并进行单体型分析.候选基因直接测序检测基因突变.结果两点间连锁分析在微卫星标记D21S1252处获得最大对数优势计分(LOD)值Zmax=3.23(θmax=0.00).精细定位和单体型分析将致病基因定位于微卫星标记D21S263和D21S266之间,遗传距离约18.47厘摩(cM),染色体位置为21q22.11-q22.3.候选基因直接测序发现CRYAA基因第3外显子第347碱基一个G→A的点突变.结论本研究将一中国先天性前极白内障家系的致病基因定位于21号染色体21q22.11-q22.3区域内,并在CRYAA基因发现一个点突变与此家系共分离.
목적 대중국일상염색체현성유전선천성전겁백내장가계진행치병기인적정위여후선기인돌변검측.방법 채집가계성원외주정맥혈,제취기인조DNA.선용ABI공사제공적약400개유전표기물진행기인소묘.기인소묘분초보소묘화정세소묘량보진행.수선대이보도적선천성백내장후선구역진행초보소묘,지후재양성구역내진행정세소묘.수거경련쇄분석,초보학정치병기인소재염색체구역.재양성구역내선취경고밀도적형광표기물진행정세소묘,병진행단체형분석.후선기인직접측서검측기인돌변.결과 량점간련쇄분석재미위성표기D21S1252처획득최대대수우세계분(LOD)치Zmax=3.23(θmax=0.00).정세정위화단체형분석장치병기인정위우미위성표기D21S263화D21S266지간,유전거리약18.47전마(cM),염색체위치위21q22.11-q22.3.후선기인직접측서발현CRYAA기인제3외현자제347감기일개G→A적점돌변.결론 본연구장일중국선천성전겁백내장가계적치병기인정위우21호염색체21q22.11-q22.3구역내,병재CRYAA기인발현일개점돌변여차가계공분리.
Objective To map the gene mutation responsible for autosomal dominant inherited congenital anterior polar cataract in a Chinese family. Methods Peripheral blood samples were collected from the members in this congenital cataract family. DNA was extracted from the blood samples. A genescan was performed using approximately 400 microsatellite markers (ABI). Linkage analysis was processed to define the region of mutated gene. High density primers labeled with fluorescent stain for the positive region were adopted for fine targeting and haplotype analysis was performed. Mutation detection was carried out by sequencing candidate genes. Results The maximum two-point LOD score was obtained at D21S1252,Zmax = 3. 23 ( θmax = 0. 00). After fine targeting and haplotype analysis,the mutated gene was located within a 18. 47 cM region between D21S263 and D21S266 on chromosome 21q22.11 -q22.3. Direct sequencing of the candidate gene revealed a G→ A transition in exon 3 of CRYAA. Conclusion The present study has identified a missense mutation in CRYAA associated with congenital anterior polar cataract in a Chinese family.