Immunodeficiency with hyper-IgM.

Men are largely affected with X-linked hyper-IgM types (XHIM, HIGM1 as the most common), which are absent in women. The US National Library of Medicine's Genetics Home Reference reported in 2014 that the estimated incidence of XHIM is 2 per million newborn boys. The autosomal recessive forms types 2, 3, 4, and 5 affect men and women equally. Family history is a risk factor for HIGM1. The son of a female genetic carrier, who has the abnormal gene on one of her two X chromosomes, has a 50 percent higher risk of inheriting the disorder. No known environmental or natural risk factors are associated with immunodeficiency with hyper-IgM.