Severe microcephaly
Gene: NAA20
Comment on phenotypes: Currently there is no phenotype associated with this gene in OMIM, Gen2Phen or MONDO (13/07/2021).Created: 13 Jul 2021, 11:08 a.m. | Last Modified: 13 Jul 2021, 11:09 a.m.
Panel Version: 2.219
Not associated with a phenotype in OMIM nor Gen2Phen. Two missense variants reported as homozygotes in one family each. In silico predictions and in vitro functional studies provide evidence that these variants will adversely affect their capacity to form a NatB complex with NAA25, and in vitro acetylation assays revealed reduced catalytic activities toward different NatB substrates (PMID 34230638). Children from these two families had developmental delay, intellectual disability (mild to moderate family 1, severe family 2).
The two children in family 1 in this study had a head circumcernces of -2.3 & -1.9 SD (which is not regarded as severe microcephaly).
The three children from family 2 in this study had a head circumcernces of -3.5, -3.0 & -3.5 SD (which is regarded as severe microcephaly). Subtle dysmorphic features were also reported.
Sources: LiteratureCreated: 13 Jul 2021, 11:05 a.m. | Last Modified: 13 Jul 2021, 11:20 a.m.
Panel Version: 2.220
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
autosomal recessive developmental delay, intellectual disability, and microcephaly
Publications
Gene: naa20 has been classified as Amber List (Moderate Evidence).
Phenotypes for gene: NAA20 were changed from autosomal recessive developmental delay, intellectual disability, and microcephaly to autosomal recessive developmental delay, intellectual disability, and microcephaly
gene: NAA20 was added gene: NAA20 was added to Severe microcephaly. Sources: Literature Mode of inheritance for gene: NAA20 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: NAA20 were set to 34230638 Phenotypes for gene: NAA20 were set to autosomal recessive developmental delay, intellectual disability, and microcephaly Review for gene: NAA20 was set to AMBER