Abstract Here we describe unrelated Japanese patients with distinct novel heterozygous retinoic acid receptor beta (RARB) gene variants underlying syndromic microphthalmia-12: case 1 with a frameshift variant, c. 1205₁206del, had bilateral microphthalmia, corneal opacity, anterior segment dysgenesis, widespread multiorgan anomalies, hypotonia and cognitive impairment; case 2 with a missense variant, c. 844G>T had Peters anomaly, extreme microphthalmia, spasticity, profound psychomotor delay and refractory epilepsy. These findings highlight the need for RARB testing.
Koyanagi et al. (Mon,) studied this question.