Genetic analyses of the affected patient (III-1) and family members and in vitro functional analysis of the mutant PIGB. (A) The inherited PIGB mutation confirmed by Sanger sequencing in blood cells (homozygous) and somatic cells derived from cervix (heterozygous) of III-1 and in blood cells (heterozygous) from the patient’s mother (II-7) and aunt (II-10). The mutation was not present in blood cells from the daughter (IV-1) or uncle (II-11). (B) Functional analysis of the mutant PIGB cDNA. Mutant PIGB cDNA could not rescue the surface expression of GPI-APs through transient transfection in PIGB-deficient CHO cells. (C) SNP array analysis of chromosome 15q (Chr15) in PNH-type granulocytes from III-1 using CytoScan HD Array. The PNH clone had a CN-LOH region spanning 61 Mbp with a small deletion spanning 70 kbp, including the TM2D3 and TARSL2 genes. (D) Outcome of the CN-LOH in the patient (III-I); the inherited PIGB mutation and microdeletion became homozygous by the somatic CN-LOH.