Scientists have discovered three genes linked to skin color and the risks of severe vitamin D deficiency

Genes linked to skin color may be the strongest indicator of whether or not a person is deficient in vitamin D, a new study suggests.

The researchers found that African-American participants with a specific mutation had vitamin D levels up to three times lower than what is considered the normal range for a healthy person.

Scientists have found that low levels of vitamin D are associated with several types of cancer, including breast, colon, rectum and prostate, as well as COVID-19.

The team, from City of Hope – an independent biomedical research and treatment center based in Duarte, California – says the findings suggest that in the future, doctors could better prescribe the correct dose of vitamin D supplements and help decrease black Americans risk these diseases.

“We should not fear this new study that examines the genetics of skin color and its effects on vitamin D deficiency, because being ‘colorblind’ is what has led to the widespread health disparities that we as a society are now trying to address’ said Dr. Rick Kittles, director of the Division of Health Actions at the Beckman Research Institute of City of Hope.

Vitamin D is sometimes called a “sun vitamin” because the skin naturally creates it when exposed to the sun.

It is found in foods such as milk, cheese, egg yolk, tuna and salmon, although often in small quantities, which is why supplements are sometimes needed.

Epidemiological research has suggested that incidence and mortality rates for certain types of cancer are lower among people living in the southern latitudes, with high levels of exposure to sunlight, compared to those living in the northern latitudes.

In addition, previous studies have found that having “adequate” levels of vitamin D reduces the risk of serious complications and death from COVID-19

Furthermore, race is one of the biggest predictors of low levels of vitamin D.

“Skin color has a strong social and biological meaning – social because of race and racism and biological because more than 70% of African Americans are deficient in vitamin D, resulting in an increased risk of cancer and cardiovascular disease,” he added. Kittles.

For the study, published in the journal PLOS Genetics, the team analyzed data from 1,076 people who identified themselves as African American.

Researchers collected blood samples, which they used to analyze DNA and vitamin D levels.

They also measured the skin covering the inside of the arm using a digital reflectometer.

They analyzed three genes with strong links to skin color: SLC24A5, SLC45A2 and OCA2

All three provide instructions for producing a protein located in melanocytes, which are specialized cells that produce melanin, the pigment that determines skin color.

Black participants with a genetic variant in the gene called SLC24A5 were more likely to have vitamin D levels of 12 nanograms per milliliter (ng / mL) or less.

Normal level range between 20 and 40 ng / mL for a healthy person.

The team hopes to use their findings to create a risk score assessment that can be used in doctors’ offices one day.

For example, in the future, a doctor can assess a person’s skin tone and lifestyle and use the tool to prescribe the proper dosage of vitamin D supplements.

“This study is an example of the interaction between race and skin color in health and how, if we ignore things like a person’s skin color, we may be ignoring possible medical problems, thus contributing to disparities in the health care system,” said Kittles .

“Our study provides new insights into an easily modifiable factor, such as vitamin D supplementation and inherited genetic factors that affect vitamin D deficiency in African Americans.

“With more research, in the future doctors could offer black patients an inexpensive way to reduce the risk of vitamin deficiency, which could ultimately help protect against certain types of cancer.”