We report seven (7) extremely rare recessive variants that are potentially causal in a range of rare genetic diseases such as, DHH-associated 46,XY gonadal dysgenesis (GD) or 46,XY sex reversal 7, GNPTAB-associated mucolipidosis II alpha/beta ((ML II), BBS1-associated Bardet–Biedl Syndrome (BBS), SURF1-associated Leigh Syndrome (LS) and AP4B1-associated spastic paraplegia-47 (SPG47)from a small cohort of five unrelated Bangladeshi patients. The gene discussed is AP4B1; the disease is Leigh syndrome.