You share about 49.99 % of your genes with the guy next door. With her also the same amount. But there may be some mutations you have produced. Or received from them.
And usually mutations are rather nasty.
1. Baldness is more common in men, as testosterone sensitive form is the most common.
But geneticists still do not know what's going on there. Genes are involved, and baldness is due to mutations in several genes from one or both parents.
2. Chinese lack, in one of the rare cases of this type, a beneficial mutation that enables others to eat milk and dairy products. Chinese distaste for milk was thought to be a cultural one, until the 1960s lactose intolerance was found in many populations in Eastern and Southeastern Asian, but also some Africans. Within the past 10,000 years, the beneficial mutation spread only where dairy farming was the norm.
3. Pimples, too, are linked to a family history. If your parents experienced bad pimples, you are more likely to suffer of severe acne too.
4. Another beneficial (or bad, depending on the case) aspect is high fertility in women. Identical twins are random events, but fraternal twins emerge in families again and again.
A gene is involved in multiple eggs released during ovulation (hyperovulation).
Men carrying the gene will not necessarily father twins, as this depends on the woman, but their daughters can give birth to twins when they receive the gene. That's why twins can skip generations.
5. Heart disease, diabetes, stroke or high blood pressure come in family. If parents experienced it, children present the likelihood of developing them too.
6. Studies bind obesity to a heavy set of genes. These genes were beneficial to our ancestors, as they could store "reserves" during scarcity periods. But today, there are no shortage periods. Also, many of today's obesity cases are linked to eating too much "unhealthy" food.
7. The male "aggressive behaviors" are more likely to be encoded in genes than non-aggressive antisocial behaviors like stealing. But genes can be behind the stealing behavior in women.
8. Ten million men in the U.S. are color blind (they cannot differentiate red from green) but less than 600,000 American women have the same disability. That's because this mutation is located on the X-chromosome.
Men only have one X-chromosome, so that one is enough to induce the condition, but women have two X chromosomes, and they require the mutation in double set to experience the condition.
9. Increasing evidence links breast cancers to particular genes. Those with mutation tend to develop cancer earlier and in both breasts. The same mutations increase the risk of developing prostate, breast, pancreas and other cancers in men.
10.Half of the alcoholism risk seems to be hereditary, but the environment also plays its role. There are several genes involved, working differently from one individual to another.
11.The chin dimple is caused by an incomplete fusion of the right and left sides of the jaw when encountering on the chin area. This menton symphysis, if incomplete, appears as a dimple: it is determined by a dominant gene, and its absence by a recessive gene.