Analysis of allele-specific IGF2BP1 expression. Comparative analysis of sequence variations in B lymphoblasts of the CEPH pedigree family 1331 reveals monoallelic expression of the IGF2BP1 gene. (A) Pedigree analysis was carried out for the SNP site rs11655950 located in the 3'-UTR of the IGF2BP1 gene. Each individual is shown with CEPH family identification, sample identification and genetic information (SNP genomic DNA (gDNA) genotype- or transcript-derived genotype). Individuals with monoallelic IGF2BP1 gene expression are indicated by asterisks. If the individual is homozygous at the SNP, allele-specific expression cannot be defined. (B) Left: Genotyping results at rs11655950 with gDNA from members of CEPH family 1331. gDNA was analyzed using the TaqMan SNP Genotyping Assay. This assay discriminates between sequence variants using two allele-specific probes carrying two different fluorophores, VIC and FAM. Individuals coded in red and green represent cell lines that are homozygous for alleles A and G, respectively. Orange-labeled individuals contain both A and G alleles at SNP rs11655950 and represent informative cell lines used for further analysis of monoallelic expression. Diamonds indicate cDNA samples, and black × indicates averaged triplicates of a no-template control (NTC) near the origin of the graph. Right: Genotyping results of transcript-derived cDNA from heterozygous B lymphoblasts. Individuals are color-coded in the figure key. No-RT controls (No RT) from cDNA synthesis are shown near the origin of the graph and are indicated by a black X. Control samples (standards) of stem cell lines previously genotyped as homozygous AA, heterozygous AG and homozygous GG were plotted and are indicated by diamonds.