NM_015909.4:c.680A>C
Variant summary
Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3PP5
The NM_015909.4(NBAS):c.680A>C(p.His227Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,720 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_015909.4 missense
Scores
Clinical Significance
Conservation
Publications
- infantile liver failure syndrome 2Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
- short stature-optic atrophy-Pelger-Huët anomaly syndromeInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Illumina, Labcorp Genetics (formerly Invitae), G2P
Genome browser will be placed here
ACMG classification
Our verdict: Uncertain_significance. The variant received 4 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152174Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.00000796 AC: 2AN: 251406 AF XY: 0.00000736 show subpopulations
GnomAD4 exome AF: 0.00000205 AC: 3AN: 1461546Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2AN XY: 727100 show subpopulations
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152174Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0AN XY: 74344 show subpopulations
ClinVar
Submissions by phenotype
Infantile liver failure syndrome 2 Pathogenic:2
- -
- -
not provided Pathogenic:1Uncertain:1
This sequence change replaces histidine, which is basic and polar, with proline, which is neutral and non-polar, at codon 227 of the NBAS protein (p.His227Pro). This variant is present in population databases (rs748880753, gnomAD 0.003%). This missense change has been observed in individual(s) with acute liver failure (PMID: 28576691). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 424843). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on NBAS protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 31589614, 33042920, 28576691) -
not specified Uncertain:1
Variant summary: NBAS c.680A>C (p.His227Pro) results in a non-conservative amino acid change located in the Neuroblastoma-amplified sequence, N-terminal domain (IPR029145) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251406 control chromosomes (gnomAD). c.680A>C has been reported in the literature as a compound heterozygous genotype in at-least two comprehensively genotyped siblings affected with Liver Failure Acute Infantile, Type 2, and has also been subsequently cited by others (example, Regateiro_2017, Khoreva_2020). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 33042920, 28576691). Two submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. One submitter classified the variant as likely pathogenic, and one submitter classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at