Paternal segmental isodisomy of centromeric region on chromosome 1 as a cause of juvenile hemochromatosis

Juvenile hemochromatosis type 2A in the studied patient was caused by a homozygous mutation c.196G>T (p.G66*) in hemojuvelin. Homozygous state for this mutation evolved through interstitial segmental isodisomy encompassing the centromeric region of chromosome 1 accompanying its paternal disomy. The disomy resulted into normal karyotype SNP genotyping was performed on 3 samples - family trio. Affymetrix GeneChip Command Console software was used for image processing and CEL files were processed by Affymetrix GTC using the BRLMM-P-Plus algorithm and regional GC correction configuration for Copy Number/LOH analysis. The HapMap270 file supplied by Affymetrix was used as the reference.