X-连锁慢性肉芽肿病的植入前遗传学检测

Preimplantation genetic testing for X-linked chronic granulomatous disease

目的 采用多重置换扩增结合单体型分析及致病基因检测进行X-连锁慢性肉芽肿病的植入前遗传学检测。方法 利用位于CYBB基因两侧的16个短串联重复序列位点对一个X-连锁慢性肉芽肿病的家系构建单体型进行分析。活检的胚胎细胞通过多重置换扩增技术进行全基因组扩增,利用扩增产物检测具有多态性的STR位点与CYBB基因,同时采用位点Amel进行性别诊断。结果 对一个家系共进行了2个周期的PGT,家系分析结果显示7个STR位点具有多态性。共对16个胚胎进行了诊断,均获得诊断结果,诊断效率为100%,其中8个为正常胚胎,1个为携带者,7个为异常胚胎。全基因组扩增成功率100%,后续PCR成功率为99.3%(143/144),ADO率为14.0%(6/43)。先后进行了三次胚胎移植,末次移植后获得单胎妊娠,最终足月顺产一个不携带致病基因的健康男婴。结论 基于多重置换扩增产物对短串联重复序列进行连锁分析结合致病基因检测可对X连锁慢性肉芽肿病进行准确且有效的植入前遗传学检测。

Objective To perform preimplantation genetic testing(PGT)for X-linked chronic granulomatosis using multiple displacement amplification(MDA)combined with haplotype analysis and pathogenic gene detection.Methods Sixteen short tandem repeat markers flanking both sides of CYBB gene were applied to construct haplotype analysis.Whole genome amplification was based on multiple displacement amplification and its product was further submitted to polymerase chain reaction and capillary electrophoresis to detect polymorphic STR sites and CYBB gene.The sex was diagnosed by the Amel locus.Results Two cycles of PGT were performed for a family.The pedigree analysis found seven polymorphic STR loci informative.A total of 16 embryos were diagnosed,of which 8 were genetically normal,1 was carrier and 7 were abnormal.The diagnostic efficiency was 100%.The MDA success rate was 99.3%(143/144)and the allele drop-out rate was 14.0%(6/43).A total of six transplantable blastocysts and three embryo transfer cycles were carried out for the patient,resulting in a single pregnancy and healthy baby boy at full term.Conclusion Multiple displacement amplification combined with specific amplification of pathogenic gene and haplotype analysis are effective and efficient in preimplantation genetic testing for X-linked chronic granulomatosis.