A 19 year old female with a complex phenotype suggestive of a mitochondrial disorder had mitochondrial DNA sequencing performed three times at an outside institution, all with inconclusive results due to “multiple heteroplasmic positions”. Mitochondrial genome sequencing was performed here revealing 6 benign homoplasmic and 21 benign variants at 10-20% heteroplasmy. When variants are stratified by frequency, this patient appears to have two distinct haplogroups (Figs A-B). Normally individuals have only one haplogroup, which is maternally inherited.
|Jaime Lopes, Ph.D.
Fellow, Laboratory Genetics and Genomics
|Linda Hasadsri, M.D., Ph.D.
Consultant, Laboratory Genetics and Genomics
Assistant Professor of Laboratory Medicine and Pathology
Mayo Clinic College of Medicine and Science