Fig. 1
From: Characteristics and mechanisms of mosaicism in prenatal diagnosis cases by application of SNP array
SNP array results and mechanisms for mosaic trisomy 16. The log R ratio indicates an increase in copy number, between two and three copies. Additional shifts in the B allele frequency are observed, corresponding to a shift in B allele frequency from 0% towards 33% (in the case of AA in the euploid cell line and AAB in the trisomic cell line), and a shift from 100% toward 66% (in the case of BB in the euploid cell line and ABB in the trisomic cell line). The additional haplotypes are visible near the centromere, consistent with a meiosis I nondisjunction. The crossovers were in 16p12.3 and 16q22.1, indicating that these loci were hot spot of recombination. A Mosaic trisomy 16 in case 5 arose from meiosis I with the presence of five visible crossovers. The proportion of cells exhibiting mosaic trisomy 16 was 20%. B Mosaic trisomy 16 in case 6 arose from meiosis I with 3 crossovers. The proportion of cells exhibiting mosaic trisomy 16 was 30%. C Mosaic trisomy 16 of case 7 arose from meiosis I with 4 crossovers. The proportion of cells exhibiting mosaic trisomy 16 was 20%