OBJECTIVETo assess the value of combined BACs-on-Beads(BoBs) and chromosomal karyotyping for the diagnosis of women with high-risk pregnancy.

METHODSFor 1371 women with singleton pregnancy and various indications for prenatal diagnosis, karyotyping and BoBs were simultaneously applied on their amnionic fluid samples.

RESULTSIn total 23 cases of trisomy 21, 11 cases of trisomy 18, 5 cases of sex chromosome aneuploidies, 6 cases of microdeletions/microduplications, 2 cases of chimeric chromosomes and 1 case of structural chromosomal abnormality were detected by the BoBs assay, among which the 6 microdeletions/microduplications were not detected by karyotyping. Karyotyping analysis has identified an extra yield of 19 chromosomal abnormalities and 34 chromosomal polymorphisms.

CONCLUSIONCombined use of BoBs and chromosomal karyotyping can improve the detection rate of fetal chromosomal abnormalities including microdeletions/microduplications, which should find a wider use in the clinics.

Adult ; Chromosome Aberrations ; Chromosome Disorders ; genetics ; Female ; Humans ; Karyotyping ; Middle Aged ; Pregnancy ; Prenatal Diagnosis ; methods

OBJECTIVE: To analyze the genotype and phenotype of a sibpair with partial deletion of SATB2 gene caused by 2q33.1 microdeletion. METHODS: Both children have featured mental retardation and development delay, and were subjected to karyotyping, single nucleotide microarray (SNP array) and real-time fluorescence quantitative PCR analysis. Karyotyping and SNP Array analysis were also carried out on their parents to verify the origin of mutation. RESULTS: Both sibs had a normal karyotype. SNP array showed that sib 1 had arr[hg19]2q33.1(200 192 328 - 200 197 269)×1 (4.9 kb), 2q35 (218 105 663 - 218 816 675)×3 (711 kb), while sib 2 had arr[hg19]2q33.1(200 192 328 - 200 197 269)×1 (4.9 kb), 2q35 (218 105 663-218 810 908)×3 (705.2 kb). The deletion has partially overlapped with that of 2q33.1 microdeletion syndrome and involved part of the SATB2 gene. The result of real-time fluorescence quantitative PCR assay was consistent with that of SNP assay. The duplication has originated from their father and has not been associated with any disease phenotypen. CONCLUSION Both sibs have carried partial deletion of SATB2 gene and had similar clinical phenotypes. Haploinsufficiency of such gene probably underlies the clinical manifestations in both patients.
Child ; Chromosome Deletion ; Chromosome Disorders ; Chromosomes, Human, Pair 2 ; Genetic Testing ; Humans ; Karyotyping ; Matrix Attachment Region Binding Proteins ; genetics ; Phenotype ; Transcription Factors ; genetics