Biallelic germline mutations in <i>RTEL1</i> (regulator of telomere elongation helicase 1) result in pathologic telomere erosion and cause dyskeratosis congenita.
RTEL1 deficiency has recently been described as a major genetic etiology, but the molecular basis and clinical consequences of RTEL1-associated DC are incompletely characterized.
RTEL1, an established locus for dyskeratosis congenita, harbored significantly more new damaging and missense variants at conserved residues in cases than in controls (P = 1.6 × 10(-6)).
Several studies have recently shown that germline mutations in RTEL1, an essential DNA helicase involved in telomere regulation and DNA repair, cause Hoyeraal-Hreidarsson syndrome (HHS), a severe form of dyskeratosis congenita.
FANCJ belongs to a conserved iron-sulfur (Fe S) cluster family of helicases important for genomic stability including XPD (nucleotide excision repair), DDX11 (sister chromatid cohesion), and RTEL (telomere metabolism), genetically linked to xeroderma pigmentosum/Cockayne syndrome, Warsaw breakage syndrome, and dyskeratosis congenita, respectively.
A recessive founder mutation in regulator of telomere elongation helicase 1, RTEL1, underlies severe immunodeficiency and features of Hoyeraal Hreidarsson syndrome.
This study further implicates RTEL1 in the etiology of DC/HH and immunodeficiency, and identifies the first known homozygous autosomal recessive disease-associated mutation in RTEL1.