rs72557937
Variant summary
Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate
The NM_001395413.1(POR):c.841C>A(p.Pro281Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000223 in 1,612,890 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 Uncertain significance (★★).
Frequency
Consequence
NM_001395413.1 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Uncertain_significance. Variant got 4 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
POR | NM_001395413.1 | c.841C>A | p.Pro281Thr | missense_variant | Exon 9 of 16 | ENST00000461988.6 | NP_001382342.1 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.000151 AC: 23AN: 152106Hom.: 0 Cov.: 33
GnomAD3 exomes AF: 0.0000402 AC: 10AN: 248958Hom.: 0 AF XY: 0.0000296 AC XY: 4AN XY: 135140
GnomAD4 exome AF: 0.00000890 AC: 13AN: 1460666Hom.: 0 Cov.: 32 AF XY: 0.00000826 AC XY: 6AN XY: 726598
GnomAD4 genome AF: 0.000151 AC: 23AN: 152224Hom.: 0 Cov.: 33 AF XY: 0.0000940 AC XY: 7AN XY: 74442
ClinVar
Submissions by phenotype
not specified Uncertain:1
Variant summary: POR c.841C>A (p.Pro281Thr) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-05 in 248958 control chromosomes in gnomAD. This frequency is not significantly higher than estimated for a pathogenic variant in POR causing Congenital Adrenal Hyperplasia (4e-05 vs 0.00091), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.841C>A in individuals affected with Congenital Adrenal Hyperplasia has been reported. At least one publication reports experimental evidence evaluating an impact on protein function. Comparing to normal activity of WT, this variant results in 32% of NADPH oxidation and 16% of Cytochrome C reduction in in-vitro assays (example: Huang_2008). Other indirect evidence suggests this variant reduced activity of various P450 enzymes (example: Agrawal_2008). The following publications have been ascertained in the context of this evaluation (PMID: 18551037, 18230729). One submitter has cited clinical-significance assessments for this variant to ClinVar after 2014 and has classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Congenital adrenal hyperplasia due to cytochrome P450 oxidoreductase deficiency Uncertain:1
This sequence change replaces proline, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 284 of the POR protein (p.Pro284Thr). This variant is present in population databases (rs72557937, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with POR-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. Experimental studies have shown that this missense change affects POR function (PMID: 18230729, 18551037, 31669572). 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. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at