There is likely no indication of a gene causing any of a vast number of congenital problems.
“Birth defects may be the result of genetic or environmental factors. This includes errors of morphogenesis, infection, epigenetic modifications on a parental germline, or a chromosomal abnormality.
“Animal studies indicate that the mother’s (and likely the father’s) diet, vitamin intake, and glucose levels prior to ovulation and conception have long-term effects on fetal growth and adolescent and adult disease. Animal studies have shown that paternal exposures prior to conception and during pregnancy result in increased risk of certain birth defects and cancers. This research suggests that paternal food deprivation, germ line mutations, alcohol use, chemical mutagens, age, smoking habits and epigenetic alterations can affect birth outcomes.”
I agree. Environment can open up different doors for different folks, but people say no all the time to all manner of things.