Mutations |
2 mutations
Species: human
Mutation name:
type: naturally occurring
fertility: subfertile
Comment: Large-scale genomic analyses link reproductive aging to hypothalamic signaling, breast cancer susceptibility and BRCA1-mediated DNA repair. Day FR et al. (2016) Menopause timing has a substantial impact on infertility and risk of disease, including breast cancer, but the underlying mechanisms are poorly understood. We report a dual strategy in ∼70,000 women to identify common and low-frequency protein-coding variation associated with age at natural menopause (ANM). We identified 44 regions with common variants, including two regions harboring additional rare missense alleles of large effect. We found enrichment of signals in or near genes involved in delayed puberty, highlighting the first molecular links between the onset and end of reproductive lifespan. Pathway analyses identified major association with DNA damage response (DDR) genes, including the first common coding variant in BRCA1 associated with any complex trait. Mendelian randomization analyses supported a causal effect of later ANM on breast cancer risk (∼6% increase in risk per year; P = 3 × 10(-14)), likely mediated by prolonged sex hormone exposure rather than DDR mechanisms. //////////////////
Species: mouse
Mutation name:
type: null mutation
fertility: embryonic lethal
Comment: An essential role for REV3 in mammalian cell survival: absence of REV3 induces p53-independent embryonic death. O-Wang J et al. (2002) The REV3 gene of budding yeast encodes the catalytic subunit of DNA polymerase zeta that carries out translesion DNA synthesis. While REV3-null yeast mutants are viable and exhibit normal growth, Rev3-deficient mice die around midgestation of embryogenesis, which is accompanied by massive apoptosis of cells within the embryo proper. We have investigated whether REV3 is required for the survival of mouse cells and whether the embryonic lethality caused by REV3 deficiency can be rescued by introduction of a Rev3 transgene or by inactivation of p53, the cellular gatekeeper that regulates DNA damage-induced apoptosis. We show that Rev3(-/-) blastocysts were unable to survive and grow in culture but expression of a Rev3 transgene restored their outgrowth. Moreover, Rev3 transgene expression suppressed the apoptosis in E7.5 Rev3(-/-) embryos. The Rev3(-/-) embryonic lethality, however, was not rescued by either Rev3 transgene expression or p53 deficiency. These results reveal an essential role for REV3 in the survival and growth of mammalian cells and suggest that Rev3(-/-) embryonic death occurs in a p53-independent pathway.//////////////////
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