ABSTRACT
Van der Woude syndrome (VWS) is an autosomal dominant malformation syndrome characterized by orofacial clefting (OFC) and lower lip pits. The clinical presentation of VWS is variable and can present as an isolated OFC, making it difficult to distinguish VWS cases from individuals with non-syndromic OFCs. About 70% of causal VWS mutations occur in IRF6, a gene that is also associated with non-syndromic OFCs. Screening for IRF6 mutations in apparently non-syndromic cases has been performed in several modestly sized cohorts with mixed results. In this study, we screened 1521 trios with presumed non-syndromic OFCs to determine the frequency of causal IRF6 mutations. We identified seven likely causal IRF6 mutations, although a posteriori review identified two misdiagnosed VWS families based on the presence of lip pits. We found no evidence for association between rare IRF6 polymorphisms and non-syndromic OFCs. We combined our results with other similar studies (totaling 2472 families) and conclude that causal IRF6 mutations are found in 0.24-0.44% of apparently non-syndromic OFC families. We suggest that clinical mutation screening for IRF6 be considered for certain family patterns such as families with mixed types of OFCs and/or autosomal dominant transmission.
Subject(s)
Abnormalities, Multiple/diagnosis , Abnormalities, Multiple/genetics , Brain/abnormalities , Cleft Lip/diagnosis , Cleft Lip/genetics , Cleft Palate/diagnosis , Cleft Palate/genetics , Cysts/diagnosis , Cysts/genetics , Interferon Regulatory Factors/genetics , Lip/abnormalities , Mutation , Abnormalities, Multiple/ethnology , Abnormalities, Multiple/pathology , Adult , Asian People , Brain/pathology , Child , Cleft Lip/ethnology , Cleft Lip/pathology , Cleft Palate/ethnology , Cleft Palate/pathology , Cysts/ethnology , Cysts/pathology , DNA Mutational Analysis , Diagnosis, Differential , Female , Gene Expression , Genetic Testing , Genome-Wide Association Study , Genotype , Humans , Lip/pathology , Male , Pedigree , Phenotype , White PeopleABSTRACT
The complex chromosomal aberrations found in therapy-related acute myeloid leukemia (t-AML) suggest that the DNA double-strand break (DSB) response may be altered. In this study we examined the DNA DSB response of primary bone marrow cells from t-AML patients and performed next-generation sequencing of 37 canonical homologous recombination (HR) and non-homologous end-joining (NHEJ) DNA repair genes, and a subset of DNA damage response genes using tumor and paired normal DNA obtained from t-AML patients. Our results suggest that the majority of t-AML patients (11 of 15) have tumor-cell intrinsic, functional dysregulation of their DSB response. Distinct patterns of abnormal DNA damage response in myeloblasts correlated with acquired genetic alterations in TP53 and the presence of inferred chromothripsis. Furthermore, the presence of trisomy 8 in tumor cells was associated with persistently elevated levels of DSBs. Although tumor-acquired point mutations or small indels in canonical HR and NHEJ genes do not appear to be a dominant means by which t-AML leukemogenesis occurs, our functional studies suggest that an abnormal response to DNA damage is a common finding in t-AML.
Subject(s)
Biomarkers, Tumor/genetics , Bone Marrow/pathology , DNA Breaks, Double-Stranded , DNA Damage/genetics , Granulocyte Precursor Cells/pathology , Leukemia, Myeloid, Acute/pathology , Leukemia, Myeloid, Acute/therapy , Animals , Chromosomes, Human, Pair 8/genetics , Comet Assay , Comparative Genomic Hybridization , DNA Repair/genetics , Flow Cytometry , Gene Expression Profiling , Histones/metabolism , Humans , Leukemia, Myeloid, Acute/genetics , Mice , Mice, Inbred C57BL , Mutation/genetics , Oligonucleotide Array Sequence Analysis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Suppressor Protein p53/geneticsABSTRACT
Warfarin demonstrates a wide interindividual variability in response that is mediated partly by variants in cytochrome P450 2C9 (CYP2C9) and vitamin K 2,3-epoxide reductase complex subunit 1 (VKORC1). It is not known whether variants in calumenin (CALU) (vitamin K reductase regulator) have an influence on warfarin dose requirements. We resequenced CALU regions in a discovery cohort of dose outliers: patients with high (>90th percentile, n = 55) or low (<10th percentile, n = 53) warfarin dose requirements (after accounting for known genetic and nongenetic variables). One CALU variant, rs339097, was associated with high doses (P = 0.01). We validated this variant as a predictor of higher warfarin doses in two replication cohorts: (i) 496 patients of mixed ethnicity and (ii) 194 African-American patients. The G allele of rs339097 (the allele frequency was 0.14 in African Americans and 0.002 in Caucasians) was associated with the requirement for a 14.5% (SD +/- 7%) higher therapeutic dose (P = 0.03) in the first replication cohort and a higher-than-predicted dose in the second replication cohort (allele frequency 0.14, one-sided P = 0.03). CALU rs339097 A>G is associated with higher warfarin dose requirements, independent of known genetic and nongenetic predictors of warfarin dose in African Americans.
