Researchers found that five of the seven patients carried rare versions of ABCB6 and made little or no functional ABCB6 protein.
ABCB6 is carried on the surface of red blood cells, where 85 percent of heme is produced.
The results may provide an explanation for drug-induced cases of the disease, particularly in individuals with the rare Langereis (Lan) negative blood type whose red blood cells do not have ABCB6 protein.
Here, we reported three cases of dyschromatoses from two Chinese families initially diagnosed with DUH, until targeted gene sequencing revealed a novel ADAR1 gene mutation in one family and a recurrent ABCB6 gene mutation in another family.
The exons, splicing sites and 10 bp flanking intron sequences of ADAR1 and ABCB6 genes were captured by a gene chip commercially ordered from NimbleGen (Roche NimbleGen, Madison, WI, USA).
Some genes are relevant in the context of MDR, such as: CYP3A4, GSTP1, NR112 (PXR), 7XNRD1, ABCG2 (BCRP1), ABCB6
, UBC, CYP1A1, ABCB1 (P-gp), CASP-3, and CASP-8.