Lactate Dehydrogenase - Genetics in Humans

Genetics in Humans

The M and H subunits are encoded by two different genes:

• The M subunit is encoded by LDHA, located on chromosome 11p15.4 (Online 'Mendelian Inheritance in Man' (OMIM) 150000)
• The H subunit is encoded by LDHB, located on chromosome 12p12.2-p12.1 (Online 'Mendelian Inheritance in Man' (OMIM) 150100)
• A third isoform, LDHC or LDHX, is expressed only in the testis (Online 'Mendelian Inheritance in Man' (OMIM) 150150); its gene is likely a duplicate of LDHA and is also located on the eleventh chromosome (11p15.5-p15.3)

Mutations of the M subunit have been linked to the rare disease exertional myoglobinuria (see OMIM article), and mutations of the H subunit have been described but do not appear to lead to disease.