MT-RNR1 and Hodgkins lymphoma: However, it is important to recognize that even though MT-RNR1 m.1555A > G is not necessarily causative for HL, mitochondrial genes are transmitted maternally and therefore, identification of MT-RNR1 m.1555A > G and m.1494C > T may have substantial implications for genetic counselling and offer an early warning for maternal members in the family pedigree.