1.1. What is OMIM? Online Mendelian Inheritance in Man (OMIM^®) is a continuously updated catalog of human genes and genetic disorders and traits, with particular focus on the molecular relationship between genetic variation and phenotypic expression.

Each OMIM entry is assigned a unique six-digit number whose first digit indicates whether its inheritance is autosomal, X-linked, Y-linked, or mitochondrial: 1, autosomal dominant (entries created before May 15, 1994); 2, autosomal recessive (entries created before May 15, 1994); 3, X-linked loci or phenotypes; 4, Y- ...

Online Mendelian Inheritance in Man (OMIM™) is a comprehensive, authoritative and timely knowledgebase of human genes and genetic disorders compiled to support human genetics research and education and the practice of clinical genetics.

Material in OMIM is derived from the biomedical literature and is written by Dr. McKusick and his colleagues at Johns Hopkins University and elsewhere.