ClinVar

Description

Note this variant was found in clinical genetic testing performed by one or more labs who may also submit to ClinVar. Thus any internal case data may overlap with the internal case data of other labs. The interpretation reviewed below is that of the Stanford Center for Inherited Cardiovascular Disease. MTTI m.A4316G This is a novel variant that has not been reported in the literature. The affected region is thought to be involved in tRNA folding and tertiary structure stabilization of tRNA-Ile. Other mutations affecting tRNA structure have been implicated in cardiomyopathy (Ito et al 1992, Degoul et al 1998). Conservation analysis indicates that Adenosine is highly conserved at position 4316 with more than 95% of all mammals maintaining Adenosine at this location. A variant at the neighboring nucleotide (4317) has been identified in an individual with MELAS and a fatal infantile cardiomyopathy (Tanaka et al 1990, Ito et al 1992, Degoul et al 1998). However the 4317 was also found in 3 out of 6391 presumably healthy individuals. Mitochondrial variants, when associated with disease, are often associated with extensive variable expressivity. Thus, with the currently available data on mitochondrial mutations in general and the m.A4316G variant in the MTTI gene in particular, the contribution of this variant to this patient’s HCM cannot be determined.