11-5323394-T-C

Variant names:

• chr11-5323394-T-C
• rs755545584
• NM_033180.5:c.904A>G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_033180.5(OR51B2):​c.904A>G​(p.Ile302Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I302F) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: OR51B2 NM_033180.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -6.38
• Publications: 0 publications found

Genes affected

OR51B2 (HGNC:14703): (olfactory receptor family 51 subfamily B member 2) Olfactory receptors interact with odorant molecules in the nose, to initiate a neuronal response that triggers the perception of a smell. The olfactory receptor proteins are members of a large family of G-protein-coupled receptors (GPCR) arising from single coding-exon genes. Olfactory receptors share a 7-transmembrane domain structure with many neurotransmitter and hormone receptors and are responsible for the recognition and G protein-mediated transduction of odorant signals. The olfactory receptor gene family is the largest in the genome. The nomenclature assigned to the olfactory receptor genes and proteins for this organism is independent of other organisms. This olfactory receptor gene is a segregating pseudogene, where some individuals have an allele that encodes a functional olfactory receptor, while other individuals have an allele encoding a protein that is predicted to be non-functional. [provided by RefSeq, Jun 2015]

HBE1 (HGNC:4830): (hemoglobin subunit epsilon 1) The epsilon globin gene (HBE) is normally expressed in the embryonic yolk sac: two epsilon chains together with two zeta chains (an alpha-like globin) constitute the embryonic hemoglobin Hb Gower I; two epsilon chains together with two alpha chains form the embryonic Hb Gower II. Both of these embryonic hemoglobins are normally supplanted by fetal, and later, adult hemoglobin. The five beta-like globin genes are found within a 45 kb cluster on chromosome 11 in the following order: 5'-epsilon - G-gamma - A-gamma - delta - beta-3' [provided by RefSeq, Jul 2008]

ENSG00000239920 (HGNC:):

HBG2 (HGNC:4832): (hemoglobin subunit gamma 2) The gamma globin genes (HBG1 and HBG2) are normally expressed in the fetal liver, spleen and bone marrow. Two gamma chains together with two alpha chains constitute fetal hemoglobin (HbF) which is normally replaced by adult hemoglobin (HbA) at birth. In some beta-thalassemias and related conditions, gamma chain production continues into adulthood. The two types of gamma chains differ at residue 136 where glycine is found in the G-gamma product (HBG2) and alanine is found in the A-gamma product (HBG1). The former is predominant at birth. The order of the genes in the beta-globin cluster is: 5'- epsilon -- gamma-G -- gamma-A -- delta -- beta--3'. [provided by RefSeq, Jul 2008]

OR51B5 (HGNC:19599): (olfactory receptor family 51 subfamily B member 5) Olfactory receptors interact with odorant molecules in the nose, to initiate a neuronal response that triggers the perception of a smell. The olfactory receptor proteins are members of a large family of G-protein-coupled receptors (GPCR) arising from single coding-exon genes. Olfactory receptors share a 7-transmembrane domain structure with many neurotransmitter and hormone receptors and are responsible for the recognition and G protein-mediated transduction of odorant signals. The olfactory receptor gene family is the largest in the genome. The nomenclature assigned to the olfactory receptor genes and proteins for this organism is independent of other organisms. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.059042305).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_033180.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OR51B2	NM_033180.5	MANE Select	c.904A>G	p.Ile302Val	missense	Exon 1 of 1	NP_149420.4	A0A126GWB2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OR51B2	ENST00000624187.1	TSL:6 MANE Select	c.904A>G	p.Ile302Val	missense	Exon 1 of 1	ENSP00000485407.1	Q9Y5P1
	HBE1	ENST00000292896.3	TSL:1	c.-266-53238A>G		intron	N/A	ENSP00000292896.2	P02100
	HBE1	ENST00000380237.5	TSL:1	c.-309-41443A>G		intron	N/A	ENSP00000369586.1	P02100

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460882 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726766

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33452

American (AMR) AF: 0.00 AC: 0 AN: 44674

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26082

East Asian (EAS) AF: 0.00 AC: 0 AN: 39672

South Asian (SAS) AF: 0.00 AC: 0 AN: 86174

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53364

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111344

Other (OTH) AF: 0.00 AC: 0 AN: 60360

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.085
BayesDel_addAF	Benign	-0.39	T
BayesDel_noAF	Benign	-0.80
CADD	Benign	0.0010
DANN	Benign	0.51
DEOGEN2	Benign	0.015	T
Eigen	Benign	-2.0
Eigen_PC	Benign	-2.2
FATHMM_MKL	Benign	0.0041	N
LIST_S2	Benign	0.051	T
M_CAP	Benign	0.0041	T
MetaRNN	Benign	0.059	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.0	L
PhyloP100		-6.4
PrimateAI	Benign	0.25	T
Polyphen		0.0010	B
MutPred		0.34		Loss of methylation at K307 (P = 0.1057)
ClinPred		0.17	T
GERP RS		-8.3
Varity_R		0.026
gMVP		0.013
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs755545584; hg19: chr11-5344624; COSMIC: COSV60916499;