What are the genetic changes related to succinate-CoA ligase deficiency ?
Succinate-CoA ligase deficiency results from mutations in the SUCLA2 or SUCLG1 gene. SUCLG1 gene mutations can cause fatal infantile lactic acidosis, while mutations in either gene can cause the somewhat less severe form of the condition.  The SUCLA2 and SUCLG1 genes each provide instructions for making one part (subunit) of an enzyme called succinate-CoA ligase. This enzyme plays a critical role in mitochondria, which are structures within cells that convert the energy from food into a form that cells can use. Mitochondria each contain a small amount of DNA, known as mitochondrial DNA or mtDNA, which is essential for the normal function of these structures. Succinate-CoA ligase is involved in producing and maintaining the building blocks of mitochondrial DNA.  Mutations in either the SUCLA2 or SUCLG1 gene disrupt the normal function of succinate-CoA ligase. A shortage (deficiency) of this enzyme leads to problems with the production and maintenance of mitochondrial DNA. A reduction in the amount of mitochondrial DNA (known as mitochondrial DNA depletion) impairs mitochondrial function in many of the body's cells and tissues. These problems lead to hypotonia, muscle weakness, and the other characteristic features of succinate-CoA ligase deficiency.