Homozygous sequence variants in the WNT10B gene underlie split hand/foot malformation

Abstract Split-hand/split-foot malformation (SHFM), also known as ectrodactyly is a rare genetic disorder. It is a clinically and genetically heterogeneous group of limb malformations characterized by absence/hypoplasia and/or median cleft of hands and/or feet. To date, seven genes underlying SHFM have been identified. This study described four consanguineous families (A-D) segregating SHFM in an autosomal recessive manner. Linkage in the families was established to chromosome 12p11.1-q13.13 harboring WNT10B gene. Sequence analysis identified a novel homozygous nonsense variant (p.Gln154*) in exon 4 of the WNT10B gene in two families (A and B). In the other two families (C and D), a previously reported variant (c.300_306dupAGGGCGG; p.Leu103Argfs*53) was detected. This study further expands the spectrum of the sequence variants reported in the WNT10B gene, which result in the split hand/foot malformation.

Augmented cytotoxic, mutagenic and genotoxic response triggered by carvedilol and celecoxib combinations

It is understood that drugs regardless of their order of administration can exhibit drug interactions. Established on the fact that treatment of hypertension may last for decades and prolong usage of multiple drug regimen may induce substantial pathophysiological changes. Hence, This study was designed to evaluate the possible synergistic toxic effects of anti-hypertensive (carvedilol), and anti-inflammatory drug (celecoxib) alone and in combinations. Well-established MTT assay, Single Cell Gel Electrophoresis (SCGE) and Ames assay were employed to evaluate the toxicity at cellular level. Results from MTT assay on Vero cell line revealed that drug combinations have more pronounced anti-proliferative activity with combine IC50 value of 13.7:47.8 µg/mL. Likewise, exposure of peripheral blood mononuclear cells with drug combinations revealed significant (P<0.05) DNA damage (Class 3) in a dose dependent manner at concentrations ≥ 0.78: 2.34 µg/mL. However, carvedilol and celecoxib were non mutagenic against either mutant strain (TA 100 and TA 98) and combinations have also shown mild to moderate mutagenic potential. Nevertheless, upon addition of metabolic activation enzyme, concentration <12.5:37.5 µg/plate exhibited significant (P<0.05) mutagenicity against both tester strains. In conclusion, this study provides additional genotoxicity and mutagenicity data that could be used in considering options for formulating regimens with reduced mutagenic potential