MSX1 and tooth agenesis: The MSX1 rs8670 genetic variant, known as transition *6C > T polymorphism (see dbSNP database: http://www.ncbi.nlm.nih.gov/snp, accessed on 10 February 2022), may contribute to the aetiology of hypodontia of maxillary lateral incisors [31] and is investigated in the present study.