DHTKD1 and proximal spinal muscular atrophy: Pathogenic variants in DHTKD1 encoding dehydrogenase E1 and transketolase domain containing 1 were previously described in patients with autosomal recessive 2-aminoadipic and 2-oxoadipic aciduria (AMOXAD), a rare metabolic disorder also characterized by hypotonia, delayed psychomotor development and seizures [9,10], autosomal dominant Charcot-Marie-Tooth disease type 2 (CMT2) [11], and autosomal recessive infantile-onset spinal muscular atrophy (SMA) with cognitive delay [12].