COL 2A1基因突变致SEDC的产前分子诊断

Prenatal molecule diagnosis of spondyleopiphyseal dysplasia congenita caused by COL2A1 gene mutation.

目的本研究对COL2A1基因(typeⅡcollagen gene)G504S突变导致的先天性脊柱骨骺发育不良(SEDC)家系的1例中期妊娠者进行产前分子诊断,从而预防SEDC的发生。方法患者妻于20孕周在B超下进行羊膜囊穿刺,抽取羊水10ml,提取羊水细胞基因组DNA。选择3个多态性STR位点,即D3S1358、D16S539和D21S11,排除母体细胞污染。在此基础上,对COL2A1基因外显子23进行扩增,PCR产物进行正、反向测序。结果该例胎儿COL2A1的外显子23测序结果显示,胎儿未带有与父亲同样的COL2A1基因突变。胎儿产前基因诊断结果与B超监测结果一致。结论对于有SEDC风险的胎儿进行产前分子诊断非常重要,可以在B超诊断前了解胎儿基因型并明确诊断。

Objective： To report the prenatal molecular diagnosis for one gravida in a family with spondylepiphyseal dysplasia congenita（SEDC） caused by G504S mutation of COL2A1 gene.Methods： DNA of the fetuse was extracted from amniotic fluid at the 20 weeks of gestation respectively.Select three polymorphic STR sites,D3S1358,D16S539 and D21S11,to evacuate maternal cell contamination.Direct sequencing of the samp leswere performed after amplifying exon 23 of COL2A1 containing the potential mutation.Results： Sequncing analysis revealed the fetus did not show the mutation of COL2A1 gene.The prenatal diagnosis result of the fetus is consistent with the sonographic scan.Conclusion： Prenatal molecular diagnosis is important for the fetus with risk of SEDC and useful for genetic counseling.Genotype of fetus with risk of SEDC can be identified before sonographic scan.