Project description:We created a bioinformatics pipeline to detect uniparental disomy from whole genome sequence data of family trios. We use inheritance patterns of single nucleotide polymorphisms to identify uniparental disomy events.
Project description:Utilizing reciprocal genome-wide uniparental disomy samples presenting with Beckwith-Wiedemann and Silver-Russell syndrome-like phenotypes, we have analyzed ~0.1% of CpG dinucleotides present in the human genome for imprinted differentially methylated regions (DMRs) using the Illumina Infinium HumanMethylation27 BeadChip microarray. This approach identified 15 imprinted DMRs associated with previously characterized imprinted domains, and confirmed the maternal methylation of the RB1 DMR. In addition, we discovered two novel DMRs: a maternally methylated region overlapping the FAM50B promoter CpG island, which results in paternal expression of this retrotransposon, and a paternally methylated region located between maternally expressed ZNF597 and NAT15 genes. We analyzed reciprocal genome-wide uniparental disomy samples (one maternal UPD and three paternal UPD samples) and six different normal somatic tissues derived from the three germinal layers (lymphocytes, buccal cells, placenta, brain, muscle, and fat) .
Project description:Genomic abnormalities leading to colorectal cancer (CRC) include somatic events causing copy number aberrations (CNAs) as well as copy neutral manifestations such as loss of heterozygosity (LOH) and uniparental disomy (UPD). We studied the causal effect of these events by analyzing high resolution cytogenetic microarray data of 15 tumor-normal paired samples. We detected 144 genes affected by CNAs. A subset of 91 genes are known to be CRC related yet high GISTIC scores indicate 24 genes on chromosomes 7, 8, 18 and 20 to be strongly relevant. Combining GISTIC ranking with functional analyses and degree of loss/gain we identify three genes in regions of significant loss (ATP8B1, NARS, and ATP5A1) and eight in regions of gain (CTCFL, SPO11, ZNF217, PLEKHA8, HOXA3, GPNMB, IGF2BP3 and PCAT1) as novel in their association with CRC. Pathway analysis indicates TGF-β signaling pathway to be affected by the cytogenetic events causing CRC as evidenced by the action of genes impacted by CNAs on SMAD family of proteins. Finally, LOH and UPD collectively affected nine cancer related genes. Transcription factor binding sites on regions of >35% copy number loss/gain influenced 16 CRC genes. Our analysis shows patient specific CRC manifestations at the genomic level and that these different events affect individual CRC patients differently. Copy number analysis of Affymetrix CytoScanHD arrays was performed for 15 Tumors and 15 Adjacent Normals from Colorectal Tissue was used as reference for the study.
Project description:We describe a stromal predominant Wilms tumor with a complex, tumor specific chromosome 11 aberration: a homozygous deletion of the entire WT1 gene within a heterozygous 11p13 deletion and an additional region of uniparental disomy (UPD) limited to 11p15.5-p15.2 including the IGF2 gene. The tumor carried a heterozygous p.T41A mutation in CTNNB1. Cells established from the tumor carried the same chromosome 11 aberration, but a different, homozygous p.S45Î CTNNB1 mutation. Uniparental disomy (UPD) 3p21.3pter lead to the homozygous CTNNB1 mutation. The tumor cell line was immortalized with telomerase (TERT) and a novel triple ts mutant SV40 large T antigen (LT). This cell line is cytogenetically stable and can be grown indefinitely. It is a valuable tool to study the effect of a complete lack of WT1 in tumor cells. The tumor cell line and the immortalized cells have a limited potential for muscle/osteogenic/adipogenic differentiation similar to all other WT1 mutant cell lines. Array expression experiment of Wilms tumor cell lines
Project description:We describe a stromal predominant Wilms tumor with a complex, tumor specific chromosome 11 aberration: a homozygous deletion of the entire WT1 gene within a heterozygous 11p13 deletion and an additional region of uniparental disomy (UPD) limited to 11p15.5-p15.2 including the IGF2 gene. The tumor carried a heterozygous p.T41A mutation in CTNNB1. Cells established from the tumor carried the same chromosome 11 aberration, but a different, homozygous p.S45Δ CTNNB1 mutation. Uniparental disomy (UPD) 3p21.3pter lead to the homozygous CTNNB1 mutation. The tumor cell line was immortalized with telomerase (TERT) and a novel triple ts mutant SV40 large T antigen (LT). This cell line is cytogenetically stable and can be grown indefinitely. It is a valuable tool to study the effect of a complete lack of WT1 in tumor cells. The tumor cell line and the immortalized cells have a limited potential for muscle/osteogenic/adipogenic differentiation similar to all other WT1 mutant cell lines.
Project description:Methylation profiles of chr12-16 were generated by meDIP and array hybridisation in 3 cases with maternal uniparental disomy of chromosome 15, and three cases of paternal uniparental disomy of chromosome 15. Comparison of these profiles reveals differentially methylated (imprinted) regions on chromosome 15.
Project description:Copy number analysis was performed using genotyping microarrays for 55 choroid plexus tumors. Genomic aberrations were investigated by tumor histological classification and the pattern observed in each subgroup was further refined. Allele specific copy number analysis also allowed us to identify regions of acquired uniparental disomy with neutral copy number values.
