16-177088-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000558.5(HBA1):​c.255C>T​(p.Ser85Ser) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000716 in 1,395,696 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 7.2e-7 ( 0 hom. )

Consequence

HBA1
NM_000558.5 synonymous

Scores

2

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: -0.969

Publications

4 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: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.41).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000558.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HBA1
NM_000558.5
MANE Select
c.255C>Tp.Ser85Ser
synonymous
Exon 2 of 3NP_000549.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HBA1
ENST00000320868.9
TSL:1 MANE Select
c.255C>Tp.Ser85Ser
synonymous
Exon 2 of 3ENSP00000322421.5
HBA1
ENST00000472694.1
TSL:1
n.391C>T
non_coding_transcript_exon
Exon 1 of 2
HBA1
ENST00000487791.1
TSL:1
n.224C>T
non_coding_transcript_exon
Exon 2 of 2

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
150872
AF XY:
0.00
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
AF:
7.16e-7
AC:
1
AN:
1395696
Hom.:
0
Cov.:
26
AF XY:
0.00000144
AC XY:
1
AN XY:
692090
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32202
American (AMR)
AF:
0.00
AC:
0
AN:
38956
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25334
East Asian (EAS)
AF:
0.00
AC:
0
AN:
37492
South Asian (SAS)
AF:
0.00
AC:
0
AN:
81994
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
37184
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4074
European-Non Finnish (NFE)
AF:
9.26e-7
AC:
1
AN:
1080294
Other (OTH)
AF:
0.00
AC:
0
AN:
58166
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
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.:
31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.41
CADD
Benign
8.4
DANN
Benign
0.96
PhyloP100
-0.97
PromoterAI
0.019
Neutral

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

Other links and lift over

dbSNP: rs33996798; hg19: chr16-227087; API