rs34227486

Positions:

• chr11-5226583-G-C
• chr11-5226583-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_000518.5(HBB):​c.309C>G​(p.Asn103Lys) 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. 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. N103S) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: HBB NM_000518.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.62

Genes affected

HBB (HGNC:4827): (hemoglobin subunit beta) The alpha (HBA) and beta (HBB) loci determine the structure of the 2 types of polypeptide chains in adult hemoglobin, Hb A. The normal adult hemoglobin tetramer consists of two alpha chains and two beta chains. Mutant beta globin causes sickle cell anemia. Absence of beta chain causes beta-zero-thalassemia. Reduced amounts of detectable beta globin causes beta-plus-thalassemia. 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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr11-5226583-GTT-GGA is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HBB	NM_000518.5	c.309C>G	p.Asn103Lys	missense_variant	2/3	ENST00000335295.4	NP_000509.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HBB	ENST00000335295.4	c.309C>G	p.Asn103Lys	missense_variant	2/3	1	NM_000518.5	ENSP00000333994	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.20	T;T;.
Eigen	Uncertain	0.20
Eigen_PC	Benign	0.014
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.97	.;D;D
M_CAP	Pathogenic	0.47	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Pathogenic	0.90	D
MutationAssessor	Pathogenic	4.6	H;H;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-5.1	D;.;.
REVEL	Pathogenic	0.81
Sift	Pathogenic	0.0	D;.;.
Sift4G	Uncertain	0.0070	D;.;.
Polyphen		1.0	D;D;.
Vest4		0.95
MutPred		0.92		Gain of methylation at N103 (P = 0.0052);Gain of methylation at N103 (P = 0.0052);Gain of methylation at N103 (P = 0.0052);
MVP		0.97
MPC		0.24
ClinPred		0.99	D
GERP RS		-0.0080
Varity_R		0.84
gMVP		0.96

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

Other links and lift over

dbSNP: rs34227486; hg19: chr11-5247813;