As suggested by a linear regression model, factors including gender (B Female = 44.12, 95% CI:17.86, 70.38), older age (B ≥ 40 = −111.99, 95% CI:−174.70, −49.27), higher education level (B = 35.65, 95% CI:5.34, 65.97), WHO clinical stage (BIV = −254.53, 95% CI−298.82, −210.24), and hemoglobin (B = 5.23, 95% CI:0.25, 10.20) were significantly associated with CD4 count.The prevalence of AHD in patients was high in Iran. The gene discussed is CD4; the disease is mitochondrial DNA depletion syndrome 4a.