DNA doesn't dictate skin color or any other human trait or characteristic
https://www.npr.org/2023/04/28/1172856207/at-home-dna-test-kits-can-tell-you-many-things-race-shouldnt-be-one-of-them
Excerpt: "In the year 2000, the Human Genome Project completed their first draft of the very first sequenced human genome. It was celebrated as a major breakthrough for humanity. And in a lot of ways, genomic data has lived up to the hype–by linking hereditary diseases to particular genes, kicking off the field of gene therapy and putting personalized genetic data into the hands of individuals.
But the tests also have their limitations.
This episode, Short Wave Scientist in Residence Regina G. Barber talks to anthropologist Agustín Fuentes about the limits of at-home genetic tests and how misinformation about race and biology can come into play.
DNA test kits like the ones created by 23andMe and Ancestry.com do not emphasize the 99.9% of the human genome that is the same across humans. Instead, they focus on the 0.1% variation among humans. The tests give users results based on large geographic locations, known as continental ancestry. But as Fuentes points out, "Africa, Asia and Europe are not biological units, right? They're not even single geobiological patterns or areas or habitats or ecologies ... They are geopolitical. We named them."
Still, companies use reference populations to tell users that a percentage of their DNA belongs to individuals in a given geographic location rather than stating that the user's DNA is similar to a given group.
As Fuentes notes, there is a simple problem with trying to pull race and ethnicity from genetic tests. "There is no gene for race because race doesn't come from biology," says Fuentes. "It comes from racism.""
DNA tests are not so reliable in predicting human traits and characteristics either:
But the tests also have their limitations.
This episode, Short Wave Scientist in Residence Regina G. Barber talks to anthropologist Agustín Fuentes about the limits of at-home genetic tests and how misinformation about race and biology can come into play.
DNA test kits like the ones created by 23andMe and Ancestry.com do not emphasize the 99.9% of the human genome that is the same across humans. Instead, they focus on the 0.1% variation among humans. The tests give users results based on large geographic locations, known as continental ancestry. But as Fuentes points out, "Africa, Asia and Europe are not biological units, right? They're not even single geobiological patterns or areas or habitats or ecologies ... They are geopolitical. We named them."
Still, companies use reference populations to tell users that a percentage of their DNA belongs to individuals in a given geographic location rather than stating that the user's DNA is similar to a given group.
As Fuentes notes, there is a simple problem with trying to pull race and ethnicity from genetic tests. "There is no gene for race because race doesn't come from biology," says Fuentes. "It comes from racism.""
DNA tests are not so reliable in predicting human traits and characteristics either:
My comment: DNA transcription is regulated and controlled by epigenetic mechanisms. Look at the following picture; in order for a gene to be transcribed (to be read), several epigenetic mechanisms and factors contribute the transcription procedure. The transcription start site, intensity, timing and end site are all regulated by epigenetic mechanisms and factors.
Skin color is based on pigment levels produced by transcription of several genes such as HERC2, OCA2, MC1R, ASIP, SLC45A2, IRF4, TYR, TYRP1, GRM5, HYAL1 sekä HYAL3 genes. Every person has all of these genes so every person is able to produce any possible skin color. The question is, which genes are epigenetically expressed and at what level. For all of these genes there are promoters, enhancers, transcription factors and other mechanisms that are also regulated by epigenetic mechanisms and factors. Most of these pigment related genes are also associated with immune system. Methylation profiles of immune system related genes are not erased during embryonic development which means that skin color is likely inherited by epigenetic information. Histone epigenetic markers are also a strong candidate in question, how skin color is inherited. LncRNAs transmit epigenetic markers in extracellular vesicles from parents to offspring. This discovery breaks the Weismann barrier and emphasizes the role of epigenetics in inheritance.
