chr16-173294-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000517.6(HBA2):​c.265G>A​(p.Ala89Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000013 in 1,537,160 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: 𝑓 0.0000070 ( 0 hom., cov: 24)
Exomes 𝑓: 7.2e-7 ( 0 hom. )

Consequence

HBA2
NM_000517.6 missense

Scores

7
7
2

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 7.43
Variant links:
Genes affected
HBA2 (HGNC:4824): (hemoglobin subunit alpha 2) The human alpha globin gene cluster located on chromosome 16 spans about 30 kb and includes seven loci: 5'- zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 - alpha-1 - theta - 3'. The alpha-2 (HBA2) and alpha-1 (HBA1) coding sequences are identical. These genes differ slightly over the 5' untranslated regions and the introns, but they differ significantly over the 3' untranslated regions. Two alpha chains plus two beta chains constitute HbA, which in normal adult life comprises about 97% of the total hemoglobin; alpha chains combine with delta chains to constitute HbA-2, which with HbF (fetal hemoglobin) makes up the remaining 3% of adult hemoglobin. Alpha thalassemias result from deletions of each of the alpha genes as well as deletions of both HBA2 and HBA1; some nondeletion alpha thalassemias have also been reported. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.988

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
HBA2NM_000517.6 linkuse as main transcriptc.265G>A p.Ala89Thr missense_variant 2/3 ENST00000251595.11 NP_000508.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
HBA2ENST00000251595.11 linkuse as main transcriptc.265G>A p.Ala89Thr missense_variant 2/31 NM_000517.6 ENSP00000251595 P1
HBA2ENST00000484216.1 linkuse as main transcriptc.235G>A p.Ala79Thr missense_variant 2/21 ENSP00000495899
HBA2ENST00000482565.1 linkuse as main transcriptn.401G>A non_coding_transcript_exon_variant 1/21
HBA2ENST00000397806.1 linkuse as main transcriptc.169G>A p.Ala57Thr missense_variant 2/32 ENSP00000380908

Frequencies

GnomAD3 genomes
AF:
0.00000699
AC:
1
AN:
143110
Hom.:
0
Cov.:
24
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000149
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
7.17e-7
AC:
1
AN:
1394050
Hom.:
0
Cov.:
27
AF XY:
0.00000144
AC XY:
1
AN XY:
692368
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.25e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000699
AC:
1
AN:
143110
Hom.:
0
Cov.:
24
AF XY:
0.0000144
AC XY:
1
AN XY:
69640
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000149
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.36
D
BayesDel_noAF
Pathogenic
0.29
CADD
Uncertain
23
DANN
Uncertain
1.0
DEOGEN2
Benign
0.076
.;T
Eigen
Uncertain
0.44
Eigen_PC
Uncertain
0.26
FATHMM_MKL
Uncertain
0.92
D
M_CAP
Pathogenic
0.83
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
0.84
D
MutationTaster
Benign
1.0
D;D
PrimateAI
Uncertain
0.73
T
PROVEAN
Uncertain
-3.6
D;D
REVEL
Pathogenic
0.82
Sift
Pathogenic
0.0
D;D
Sift4G
Uncertain
0.016
D;D
Vest4
0.55
MutPred
0.94
Gain of ubiquitination at K91 (P = 0.0804);.;
MVP
1.0
MPC
2.3
ClinPred
1.0
D
GERP RS
3.3
gMVP
0.87

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.

Other links and lift over

dbSNP: rs281864869; hg19: chr16-223293; API