APOA1 and apolipoprotein A-I deficiency: Compound homozygous, heterozygous, and heterozygous mutations in the APOA1 gene cause familial hypoalphalipoproteinemia (Hypoalphalipoproteinemia, Primary, 2) (OMIM, 618,463), which also includes the Combined Apo-I and apoC-III, both being autosomal recessive diseases [4,16,31].