Application Study Of SNP Microarray In Spontaneous Abortion And Fetal Nervous System Abnormality

Objective To explore the application significance of single nucleotide polymorphism(SNP)microarray technology in spontaneous abortion and fetal nervous system malformation,and the relationship between chromosome abnormality and spontaneous abortion and fetal nervous system abnormality.Object and Methods A total of 120 samples of spontaneous abortion were collected and detected by SNP microarray technology.The fluorescence in situ hybridization(FISH)probe marked with centromeres of chromosome16/22 was used to verify the reliability of the SNP microarray technology detection for chromosome 16/22 trisomy and its related mosaic.Additionally analyzed the relationship between the aborted fetal karyotype abnormity and age,the number of abortions,etc.Collection of 40 abnormal amniotic fluid and abortion casese of fetal nervous system abnormalities screened by Ultrasonic testing and Nuclearmagnetic resonance(NMR)were tested by SNP microarray technology,of the 40 samples,32 samples of amniotic fluid were additional analyzed by traditional karyotype.Results The detection success rate of 120 spontaneous abortion samples was 100%.A total of 70 chromosome abnormal samples were detected(58.3%),there were 42 cases of chromosome number abnormality(35%)and 16 cases of chromosome structural abnormalities(13.3%),12 cases of mosaic(10%).Of the 42 cases,there were 40 cases of Chromosome aneuploid(45,X has the highest percentage),and 2 cases of triploid.There were 9 cases of pathogenic structural abnormalities amonge the 16 cases of chromosome structural abnormalities,involved Chromosome abnormality fragment between 309 Kb to40 Mb,contains a lot of pathogenic gene.Which involved 1p36 microdeletion syndrome,8p23.1 microdeletion syndrome,Timothy and Brugada syndrome.These pathogenicity genes and microdeletion repeated syndrome can cause fetal intrauterine growth retardation,mental retardation,Cardiac anomalies and so on.16/22 trisomy and related mosaic verified by FISH technology were in agreement with the results of SNP microarray technology.Although the proportion of 16/22 related mosaic was lower than SNP microarray technology verified by FISH technology,It’s still chimera,the clinical significance is consistent.Statistical data showed that the chromosome abnormality rate in higher age group was significantly higher than in lower age group(P<0.05).However,there was no significant difference in chromosome abnormality between initial abortion and recurrent abortion(P>0.05).The detection success rate of fetal nervous system abnormality was 100%.At the same time,in 32 cases of amniotic fluid analysis,31 case cells were successfully cultured and the success rate was 96.9%.There were7 cases of chromosome abnormality(17.5%),2 cases with abnormal number(5%),5 cases of structural abnormalities(12.5%).There were Emanuelsyndrome(ES),wolf-hirschhorn syndrome(WHS)and 16p13.11 microdeletion syndrome were related to neurocognition,growth and development amonge 5 cases of structural abnormalities.32 amniotic fluid samples were both tested by traditional karyotype analysis and SNP microarray technique,The traditional karyotype analysis only detected out 2 cases of numerical chromosomal abnormalities.SNP chromosome microarray technology also found 2 cases structura1 chromosomal abnormalities in the samples of lateral ventricle and hydrocephalus additionally,and 3 cases of structura1 chromosomal abnormalities among 8 cases of abortion products of fetal nervous system abnormality.Conclusion and significance Chromosome abnormality is the main factor responsible for early spontaneous abortion,mainly due to numerical abnormality.The abnormal rate of aborted fetal chromosome abnormality in the senile group was significantly higher than that in the younger group.No significant difference exists in the chromosome abnormality between initial abortion and recurrent abortion.Chromosome abnormality,especially CNV,is closely related to fetal nervous system abnormality.SNP microarray can not only detect the numerical abnormalities of chromosome,large fragments of structural abnormalities,but also can detect tiny deletion and duplication of chromosomes improved detection rate of chromosome abnormality so as to help to fully understand the status of the chromosomal abnormalities of spontaneous abortion and fetal nervous system abnormality,which is useful to assess the risk of subsequent pregnancy and reduce the birth of the fetal nervous system anomaly...