rs35615982

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000558.5(HBA1):​c.38C>A​(p.Ala13Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as other (no stars).

Frequency

Genomes: not found (cov: 28)
Exomes 𝑓: 0.0000028 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

HBA1
NM_000558.5 missense

Scores

5
3
10

Clinical Significance

other no assertion criteria provided O:2

Conservation

PhyloP100: -0.107

Publications

10 publications found
Variant links:
Genes affected
HBA1 (HGNC:4823): (hemoglobin subunit alpha 1) 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]
HBA1 Gene-Disease associations (from GenCC):
  • alpha thalassemia spectrum
    Inheritance: AR, SD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • erythrocytosis, familial, 7
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • hemoglobin M disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Hb Bart's hydrops fetalis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hemoglobin H disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • methemoglobinemia, alpha type
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • Heinz body anemia
    Inheritance: AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.976

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HBA1NM_000558.5 linkc.38C>A p.Ala13Asp missense_variant Exon 1 of 3 ENST00000320868.9 NP_000549.1 P69905D1MGQ2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HBA1ENST00000320868.9 linkc.38C>A p.Ala13Asp missense_variant Exon 1 of 3 1 NM_000558.5 ENSP00000322421.5 P69905

Frequencies

GnomAD3 genomes
Cov.:
28
GnomAD2 exomes
AF:
0.00000606
AC:
1
AN:
164998
AF XY:
0.0000113
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AS_VQSR
AF:
0.00000279
AC:
4
AN:
1435140
Hom.:
0
Cov.:
28
AF XY:
0.00000561
AC XY:
4
AN XY:
712438
show subpopulations
⚠️ 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:
32378
American (AMR)
AF:
0.00
AC:
0
AN:
41574
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25732
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38568
South Asian (SAS)
AF:
0.0000483
AC:
4
AN:
82748
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51332
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4846
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1098644
Other (OTH)
AF:
0.00
AC:
0
AN:
59318
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.250
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
28
ExAC
AF:
0.0000170
AC:
2

ClinVar

Significance: other
Submissions summary: Other:2
Revision: no assertion criteria provided
LINK: link

Submissions by phenotype

HEMOGLOBIN J (PARIS 1) Other:1
Jul 20, 2016
OMIM
Significance:other
Review Status:no assertion criteria provided
Collection Method:literature only

- -

HEMOGLOBIN J (ALJEZUR) Other:1
Jul 20, 2016
OMIM
Significance:other
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.20
BayesDel_addAF
Pathogenic
0.38
D
BayesDel_noAF
Pathogenic
0.30
CADD
Benign
16
DANN
Benign
0.92
DEOGEN2
Benign
0.18
T
Eigen
Benign
-0.60
Eigen_PC
Benign
-0.78
FATHMM_MKL
Benign
0.38
N
LIST_S2
Benign
0.60
T
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.98
D
MetaSVM
Uncertain
0.19
D
PhyloP100
-0.11
PrimateAI
Uncertain
0.57
T
PROVEAN
Benign
-2.3
N
REVEL
Pathogenic
0.68
Sift
Uncertain
0.010
D
Sift4G
Benign
0.077
T
Vest4
0.84
MutPred
0.95
Loss of MoRF binding (P = 0.0276);
MVP
1.0
ClinPred
0.73
D
GERP RS
-0.29
PromoterAI
-0.041
Neutral
Varity_R
0.62
gMVP
0.69
Mutation Taster
=6/94
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs35615982; hg19: chr16-226753; API