Jan 2, 2025 Story by: Editor
Awareness of the disparities in access, treatment, and outcomes between Black and white Americans is common among those engaged in population-scale health research.
A closer look often reveals that these differences stem less from inherent racial factors and more from systemic racism and environmental influences. Furthermore, researchers frequently identify significant genetic differences among populations facing similar diseases but exposed to varying environmental, social, and lifestyle factors.
Recently, researchers at Cincinnati Children’s Hospital have identified two ancestry-specific gene loci linked to atopic dermatitis (AD) susceptibility in individuals of African descent. Their findings were published in HGG Advances in September 2024.
Beyond the Itch: Atopic Dermatitis and Its Impact
Atopic dermatitis, or eczema, is a chronic skin condition characterized by inflammation and intense itching. According to the National Eczema Association, approximately 31.6 million people in the U.S.—about 10.1% of the population—experience some form of eczema, with the condition most commonly occurring during early childhood.
Beyond the severe itching, the condition has broader health implications. Over half of children with severe AD eventually develop asthma, and young children with the disease are six times more likely to develop food allergies.
Although eczema affects diverse populations, most genetic studies have historically focused on individuals of European and East Asian ancestry. This new study analyzed over 1,700 biological samples from African Americans, including more than 700 individuals with AD.
Two Key Genetic Discoveries
Using admixture mapping—a genetic analysis method tailored for admixed populations such as African Americans—alongside genome-wide association analysis and joint analysis, the researchers identified two gene loci:
- rs2195989, located within the gene ANGPT1 (8q23.1).
- rs62538818, found in the intergenic region between the genes LURAP1L and MPDZ (9p23).
“These variants were not discovered using European populations, underscoring that without diverse representation, genomics research may miss critical insights, potentially leading to health disparities,” stated Dr. Tesfaye Mersha, the study’s corresponding author and leader of the Population Genetics, Ancestry, and Bioinformatics Laboratory at Cincinnati Children’s.
Dr. Mersha emphasized that understanding these genetic variations could help tailor treatments to specific populations and environmental conditions, advancing precision medicine. However, he also highlighted the limitations imposed by a lack of ancestral diversity in genomics research.
“Our findings advocate for more inclusive genomics research to ensure equitable healthcare advancements. Much more research lies ahead to translate these genetic findings into more fine-tuned AD care. Likewise, similar ancestry-specific studies are needed for many more diseases,” Dr. Mersha added.
This research underscores the critical importance of diverse representation in genomics to improve global health outcomes and reduce disparities. Source: Cincinnati Childrens
