Answer:
multifactorial transmission
Step-by-step explanation:
It is mostly assumed that one genetic trait is regulated by one gene. However, some genetic traits are controlled by more than one gene. Also, some of these genetic traits are influenced by both genes and abiotic factors such as temperature conditions, diet, lifestyle, etc. These genetic traits are said to be following the multifactorial transmission as they are regulated by more than one controlling factor.
For example, skin color in human beings is regulated by more than one gene. Exposure to light and pollution also affects the skin tone of a person. Being a multifactorial trait, skin color in human beings does not exhibit distinct categories. Rather it exhibits continuous variation and the phenotype ranges from light to very dark with many intermediate categories in between.