Do RET somatic mutations play a role in Hirschsprung disease?

To the Editor:
We read “RET Somatic Mutations Are Underrecognized in Hirschsprung Disease,” by Jiang et al., recently published in your journal, with great interest. The authors hypothesize a contribution of RET somatic mutations to Hirschsprung disease (HSCR).
HSCR is a complex inherited disorder characterized by the absence of enteric ganglia in the distal part of the colon. Several genes and loci have been described as underlying disease pathogenesis. However, variants in these genes explain no more than 20% of all cases. [...]