Reduced penetrance and variable expressivity are factors that influence the effects of particular genetic changes. These factors usually affect disorders that have an autosomal dominant pattern of inheritance, although they are occasionally seen in disorders with an autosomal recessive inheritance pattern.enetrance refers to the proportion of people with a particular genetic change (such as a mutation in a specific gene) who exhibit signs and symptoms of a genetic disorder. If some people with the mutation do not develop features of the disorder, the condition is said to have reduced (or incomplete) penetrance.
Although men have more muscle mass than women, both sexes reach their physical peak as young adults or anywhere from their late 20's to early 30's, according to âHuman Development: A Life-Span Viewâ by Robert Kail and John Cavanaugh.
Your body might not be that late. Most guys hit puberty sometime from ages 9-14 -- the average age is 12. Puberty is only late if youâre 14 years old and arenât showing any signs. You might be overlooking something. You know your voice will get deeper, you'll get hair in your armpits and groin, and you'll grow taller.