Variants are typically heterozygous or homozygous, in rare cases variants may be somatic mosaic (early post-zygotic event)

Assessment of variants for pathogenicity in diagnosis, prognosis, prevention, reproductive planning or treatment

Variants have utility for familial testing, including determining carrier status or identifying other at-risk family members. Variants may also be useful for determining genomic regions with absence of homozygosity (due to consanguinity or uniparental disomy)

Detectable variant allele frequency can have a wide range in tumour tissue

Assessment of variants for utility in diagnosis, or for prognostic or therapeutic purposes

Typically no familial risk, although variants at allelic frequencies consistent with germline heterozygous or homozygous variants may be identified

Detectable variant allele frequency can have a wide range in tissue tested (due to homoplasmy or heteroplasmy)

Assessment of variants for pathogenicity in diagnosis or prognosis requires haplogroup analysis

Familial risk via maternal inheritance only

Variants have utility for familial testing, including determining carrier status or identifying other at-risk family members