Table:

Variable clinical characteristics in children with DNM1L variants.

	Published Study (author)	Age at Onset	Age at Reporting	Symptoms	Microscopy / Mitochondrial Analysis	Gene variants
1	Nasca et al, 2016 5 Sibling 1	1 year	Alive at age 16 years	Developmental delay, strabismus, ataxia, spasticity, dysarthria.	Elongated fibroblast mitochondrial morphology with a filamentous network. Peroxisomes were larger and less uniformly distributed in the cytoplasm.	c.106A>G (p.Ser36Gly) c.346_347delGA (p.Glu116Lysfs*6) compound heterozygous recessive (parents were unaffected heterozygous carriers)
2	Nasca et al, 2016 5 Sibling 2	1 year	Alive at age 3 years	Developmental delay, strabismus, ataxia, spasticity, dysarthria.	No pathology reported.	c.106A>G (p.Ser36Gly) c.346_347delGA (p.Glu116Lysfs*6) compound heterozygous recessive (parents were unaffected heterozygous carriers)
3	Yoon et al, 20167 Sibling 1	Birth	Died at 3 weeks	Hypotonia and apnea at birth.	Giant mitochondria in neurons with reduced myelination. Reduced staining of DNM1L protein in sural nerves.	c.261dup (p.Trp88Metfs*), c.385_386del (p.Glu129Lys*6) compound heterozygous recessive (parents were unaffected heterozygous carriers)
4	Yoon et al, 20167 Sibling 2	Birth	Died at 8 days	Hypotonia and apnea at birth.	Giant mitochondria in neurons with reduced myelination. Reduced staining of DNM1L protein in sural nerves.	c.261dup (p.Trp88Metfs*), c.385_386del (p.Glu129Lys*6) compound heterozygous recessive (parents were unaffected heterozygous carriers)
5	Chao et al, 20169 Case 1	5 months	Died at 5 years	Developmental delay, refractory epilepsy, status epilepticus.	Muscle biopsy had reduced activity in complexes I, III, IV, and had mitochondrial pleomorphism.	c.1048G>A (p.G350R), de novo dominant
6	Sheffer et al, 20168	Birth	Alive at 2 years	Microcephaly, development delay, insensitivity to pain.	Decreased activity of complex IV. Elongated mitochondria, normal peroxisomes.	c.1084G>A, (p.Gly362Ser) de novo dominant
7	Vanstone et al, 20154	6 months	Alive at 7 years	Developmental delay, refractory epilepsy.	Hyperfused mitochondrial network morphology.	c.1085G→A (p.Gly362Asp) de novo dominant
8	Chao et al, 20169 Case 2	Birth	Died at 10 months	Hypotonia and apnea at birth, microcephaly, absence of corpus callosum, hydrocephalus, persistently elevated lactate.	Biopsy declined.	c.1135G>A, (p.E379K) de novo dominant
9	Waterham et al., 20073	6 days	Died at 37 days	Microcephaly, elevated lactate and very long chain fatty acids, optic atrophy.	Elongated, tubular mitochondria.	c.1184C→A (Ala395Asp) de novo dominant
10	Fahrner et al, 20166 Case 1	4 years	Alive at age 8 years	Focal status into generalized status epilepticus, refractory epilepsy, cognitive/motor delays.	Expression of mutant allele in mouse cells resulted in elongated tubular mitochondrial morphology.	c.1207C>T (p.R403C), de novo dominant
11	Fahrner et al, 20166 Case 2	5 years	Alive at age 6 years	Focal status into generalized status epilepticus, now neurological devastated with myoclonus.	No pathology reported.	c.1207C>T (p.R403C) de novo dominant
12	Zaha et al, 201610	6 months	Died at 18 months	Severe hypotonia, development delay, elevated CSF lactate, infantile spasms and suppression-burst EEG.	Elongation of peroxisomes and mitochondria of patient’s fibroblasts.	c.1217T>C (p.Leu406Ser) de novo dominant
13	Our patient described herein	18 months	Died at 13 years	Developmental delay, paroxysmal dystonia, super refractory myoclonic status epilepticus.	Elongated, tubular mitochondria.	c.1207C>T (p.R403C), de novo dominant