A novel heterozygous de novo NTN1 missense variant was identified in a patient with chorioretinal coloboma, sensorineural deafness and polydactyly, through screening of micropthalmia anophthalmia coloboma (MAC) patients in the Genomics England 100 000 Genomes Project dataset. The gene discussed is NTN1; the disease is sensorineural hearing loss disorder.