In African-American women four genetic variants that confer an increased risk of systemic lupus erythemathosus (lupus) have been identified by scientists.
The study conducted by researchers from Boston University's Slone Epidemiology Center is believed to be the first to comprehensively assess the association between genetic variants in the MHC region and risk of lupus in African American women.
The findings were based on the ongoing Black Women's Health Study, a prospective study of the health of 59,000 African American women conducted by the researchers since 1995.
It has been known that the MHC region in chromosome 6 carries genetic factors associated with several autoimmune diseases.
The researchers genotyped more than 1,500 genetic variants single nucleotide polymorphisms (SNPs) in 400 lupus cases and 800 controls.
They found four independent SNPs associated with higher risk of lupus.
Through the construction of a genetic score consisting of those four SNPs, the researchers found that risk of lupus increased by almost 70 percent for each extra high risk allele.
"Taken together, our results and previous genome-wide association studies in European and east Asian ancestry populations show that women of different ancestral origins may share some genetic components for the risk of lupus," said lead author Edward A. Ruiz-Narvaez, ScD, an assistant professor of epidemiology at Boston University School of Medicine.
The study has been currently published on-line in Human Genetics.