The Application of SNP Microarray Technique in Fetal Central Nervous System Abnormality

Objective: To explore the application significance of SNP microarray technique in fetal central nervous system deformity and the relationship between chromosome abnormality and fetal nervous system abnormality. Methods: Collection of 40 abnormal amniotic fluid and abortion casese of fetal nervous system abnormalities sereened by Ultrasonic testing and Nuclear magnetic resonance (NMR) were tested by SNP microarray technology, of the 40 samples, 32 samples of amniotic fluid were additionally analyzed with traditional karyotype. Results: The success rate of fetal nervous system anomaly detection was 100%. At the same time, in 32 cases of amniotic fluid analysis, 31 cases were successfully cultured, and the success rate was 96.9%. There were 7 cases of chromosome abnormality (17.5%), 2 cases with abnormal number(5%), 5 cases of structural abnormalities（12.5%）.32 samples of amniotic fluid were tested both by traditional karyotype analysis and SNP microarray technique, the traditional karyotype analysis only found 2 cases of numerical chromosomal abnormalities. SNP chromosome microarray technology also found 2 cases structura1 chromosomal abnormalities in the sample of lateral ventricle and hydrocephalus. Additonally detected out 3 cases of structura1 chromosomal abnormalities among 8 cases of abortion samples with fetal nervous system abnormality. Conclusion: SNP microarray can not only detect the numerical abnormalities of chromosome and large fragments of structural abnormalities, but also detect the microdeletion and microduplation of chromosomes, so as to help fully understanding the status of the chromosomal abnormalities of fetal nervous system abnormality, Particularly, gene copy number variation (CNV) is closely related to fetal central nervous system abnormality.