Although GHD due to genetic disorders is considered to be extremely rare (0.06% of total IGHD), the incidence reaches high levels (9.8%) among Severe Cases.
Thus IGHD 1A is best described as being complete GHD caused by severe loss of function GH1 gene mutations rather than being limited to only those having GH1 gene deletions.
Therefore, for these reasons it is recommended that all patients with GHD should undergo testing for genetic mutations within the genes associated with IGHD, CPHD and SOD.