Congenital tooth agenesis impairs masticatory function and aesthetics and adversely affects craniofacial development. Although largely considered genetic in origin, its exact etiology remains unclear. This study reports three familial cases of nonsyndromic congenital tooth agenesis (NSTA). Whole genome sequencing (WGS) revealed five pathogenic variants: filamins-B (FLNB) (c.5186C>A, p.Ser1729Ter), methylcrotonyl coenzyme a carboxylase 2 (MCCC2) (c.91C>T, p.Gln31Ter; c.484C>T, p.Gln162Ter; c.340C>T, p.Gln114Ter), laminin subunit alpha 2 (LAMA2) (c.1084A>T, p.Arg362Ter), cathepsin C (CTSC) (c.748C>T, p.Arg250Ter), and chromatin remodeling protein microrchidia family CW-type zinc finger 4 (MORC4) (c.1726C>T, p.Arg576Ter). Among these variants, LAMA2 was associated with a severe tooth agenesis phenotype. The findings offer novel clues toward understanding the etiopathogenesis of this condition.
