Insight into ALKBH8-related intellectual developmental disability based on the first pathogenic missense variant.
Hum Genet
; 141(2): 209-215, 2022 Feb.
Article
em En
| MEDLINE
| ID: mdl-34757492
ABSTRACT
ALKBH8 is a methyltransferase that modifies tRNAs by methylating the anticodon wobble uridine residue. The syndrome of ALKBH8-related intellectual developmental disability (MRT71) has thus far been reported solely in the context of homozygous truncating variants that cluster in the last exon. This raises interesting questions about the disease mechanism, because these variants are predicted to escape nonsense mediated decay and yet they appear to be loss of function. Furthermore, the limited class of reported variants complicates the future interpretation of missense variants in ALKBH8. Here, we report a consanguineous family in which two children with MRT71-compatible phenotype are homozygous for a novel missense variant in the methyltransferase domain. We confirm the pathogenicity of this variant by demonstrating complete absence of ALKBH8-dependent modifications in patient cells. Targeted proteomics analysis of ALKBH8 indicates that the variant does not lead to loss of ALKBH8 protein expression. This report adds to the clinical delineation of MRT71, confirms loss of function of ALKBH8 as the disease mechanism and expands the repertoire of its molecular lesions.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Deficiências do Desenvolvimento
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Mutação de Sentido Incorreto
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Homólogo AlkB 8 da RNAt Metiltransferase
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Deficiência Intelectual
Tipo de estudo:
Prognostic_studies
Limite:
Child
/
Female
/
Humans
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Male
Idioma:
En
Revista:
Hum Genet
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Arábia Saudita