Family pedigree. The affected individual is indicated by the solid symbol and unaffected relatives by open symbols. The amino acids at codon 1925 of ABCA1 are shown for each individual tested (R/R, homozygote; R/Q heterozygote). Individual I.1 died following a myocardial infarct and previously had undergone amputation of his right arm following an accident without excessive bleeding, and thus is likely to be unaffected.