Many fold effects of a gene refers to

Many fold effects of a gene are referred to as Pleiotropy.
“Pleiotropy” refers to the phenomenon in which a single locus affects two or more unrelated phenotypic traits and is often identified as a single mutation that affects two or more wild-type traits.
It refers to the effect that mutations in the same gene may lead to multiple, seemingly unrelated diseases. One gene controls the expression of several phenotypic traits. Phenotypes are traits that are physically expressed such as color, body shape and height.