Are Redhead and Blonde Genes Becoming Extinct?

Is it true that the gene for red hair is becoming extinct?

What factors determine the prevalence of red and blonde hair in a population?

How do genes exhibit different patterns of inheritance, and how does this impact the diversity of traits?

Answer:

No, the gene for red hair is not becoming extinct. Genes for red and blonde hair are not disappearing despite being recessive traits. Different patterns of inheritance and genetic variance play a role in the prevalence of these traits.

The redhead gene, as well as the blonde hair gene, are not becoming extinct, despite both being recessive traits. This is because even though these traits are less common, they are still being passed down genetically from parents to their offspring. Recessive traits, such as having red or blonde hair, only appear when an individual inherits two copies of the recessive gene, one from each parent. For instance, about 4% of people in the United States have red hair. It's just unusual, not disordered. However, it is less unusual in Scotland, where approximately 13% of the population has red hair.

Genes can exhibit different patterns of inheritance, such as dominant lethal inheritance patterns where neither heterozygotes nor homozygotes survive. In cases like these, certain alleles like the one for Huntington's disease, cause a shortened life span but may not be identified until after the person reaches reproductive age and has children. Despite the disease causing irreversible nerve cell degeneration, these genetic traits can still be maintained in the human population because they may not be expressed until the individual reaches middle age.

Genetic variance refers to the diversity of alleles and genotypes within a population. This diversity is essential for the survival and evolution of species. In the case of traits like red and blonde hair, genetic variance allows for the continued presence of these traits even if they are less common. Mutations and different inheritance patterns contribute to the genetic variance in a population.

It's important to understand that the rarity of red and blonde hair does not mean that these traits are disappearing. As long as individuals carry the recessive genes for red or blonde hair, these traits can still be passed down to future generations and remain a part of the genetic diversity of human populations.