Mild Late-Onset Sensory Neuropathy Associated with Heterozygous Missense GDAP1 Variants

Table 1

Clinical Results of individuals with a heterozygous GDAP1 missense variant.

Proband	Variants found in heterozygous state	Onset	Clinical symptoms	EMG/NCS	Family history
1	GDAP1 c.358C > T (p.Arg120Trp), classified as pathogenic	20s	Burning feet, intermittent hand numbness; decreased pinprick to midcalf	Absent sural sensory responses bilaterally	Son with high arches at age 10
2	GDAP1 c.358C > T (p.Arg120Trp), classified as pathogenic	Early 50s	Not athletic as a child, numb toes, reflexes absent	Right ulnar sensory response mildly reduced amplitude	None
3	GDAP1 c.811G > A (p.Gly271Arg), classified as pathogenic	Late 60s	Paresthesias and numbness in thumbs and toes, absent achilles reflexes	Normal	Father with neuropathy
4 (proband 3’s daughter)	GDAP1 c.811G > A (p.Gly271Arg), classified as pathogenic	40s	Fast runner as a child but had cramps; numb toes on left foot	Not performed
5	GDAP 1 c.1006G > T (p.Ala336Ser); classified as a variant of uncertain significance.	50s	Was able to run, walk, and bike as a child up until his 50s when he developed pain in both feet as if “duct tape” around it.	Left superficial peroneal and ulnar sensory and left tibial motor response mildly reduced amplitude	Mother with neuropathic pain.