Genetic Variant HOXA2:p.Gln335Gln (chr7-27100852-C-T) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_006735.4(HOXA2):c.1005G>A(p.Gln335Gln) variant causes a synonymous change. The variant allele was found at a frequency of 0.000219 in 1,614,090 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00023 ( 0 hom. )

Consequence

HOXA2
NM_006735.4 synonymous

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 3.68

Variant links:

Genes affected

HOXA2 (HGNC:5103): (homeobox A2) In vertebrates, the genes encoding the class of transcription factors called homeobox genes are found in clusters named A, B, C, and D on four separate chromosomes. Expression of these proteins is spatially and temporally regulated during embryonic development. This gene is part of the A cluster on chromosome 7 and encodes a DNA-binding transcription factor which may regulate gene expression, morphogenesis, and differentiation. The encoded protein may be involved in the placement of hindbrain segments in the proper location along the anterior-posterior axis during development. [provided by RefSeq, Jul 2008]

HOXA2 links:

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.54).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HOXA2	NM_006735.4 link	c.1005G>A	p.Gln335Gln	synonymous_variant	Exon 2 of 2	ENST00000222718.7	NP_006726.1	O43364

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HOXA2	ENST00000222718.7 link	c.1005G>A	p.Gln335Gln	synonymous_variant	Exon 2 of 2	1	NM_006735.4	ENSP00000222718.5		O43364
HOXA2	ENST00000612779.1 link	n.1835G>A		non_coding_transcript_exon_variant	Exon 1 of 1	6

Frequencies

GnomAD3 genomes

AF:

0.0000920

AC:

AN:

152198

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000191

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000127

AC:

AN:

251490

Hom.:

AF XY:

0.000110

AC XY:

AN XY:

135920

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000246

Gnomad OTH exome

AF:

0.000326

GnomAD4 exome

AF:

0.000233

AC:

340

AN:

1461892

Hom.:

Cov.:

AF XY:

0.000208

AC XY:

151

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000894

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.000289

Gnomad4 OTH exome

AF:

0.000199

GnomAD4 genome

AF:

0.0000920

AC:

AN:

152198

Hom.:

Cov.:

AF XY:

0.0000941

AC XY:

AN XY:

74350

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000191

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000229

Hom.:

Bravo

AF:

0.000136

EpiCase

AF:

0.000327

EpiControl

AF:

0.000356

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

The HOXA2 p.Gln335Gln variant was not identified in the literature but was identified in dbSNP (ID: rs779536985) and ClinVar (classified as uncertain significance by Illumina for Microtia, Hearing Impairment, and Cleft Palate). The variant was identified in control databases in 36 of 282892 chromosomes at a frequency of 0.0001273 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: Other in 2 of 7228 chromosomes (freq: 0.000277), European (non-Finnish) in 32 of 129192 chromosomes (freq: 0.000248) and Latino in 2 of 35440 chromosomes (freq: 0.000056), but was not observed in the African, Ashkenazi Jewish, East Asian, European (Finnish), or South Asian populations. The p.Gln335Gln variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. However, 3 of 4 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) predict a greater than 10% difference in splicing. However, this has not been confirmed by RNA analysis and is not predictive enough to assume pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Bilateral microtia-deafness-cleft palate syndrome

Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.54

CADD

Benign

DANN

Benign

0.91

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over