2-231108575-G-T

Position:

• chr2-231108575-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000867.5(HTR2B):​c.1388C>A​(p.Thr463Lys) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,568 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: HTR2B NM_000867.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.45

Genes affected

HTR2B (HGNC:5294): (5-hydroxytryptamine receptor 2B) This gene encodes one of the several different receptors for 5-hydroxytryptamine (serotonin) that belongs to the G-protein coupled receptor 1 family. Serotonin is a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. Serotonin receptors mediate many of the central and peripheral physiologic functions of serotonin, including regulation of cardiovascular functions and impulsive behavior. Population and family-based analyses of a minor allele (glutamine-to-stop substitution, designated Q20*) which blocks expression of this protein, and knockout studies in mice, suggest a role for this gene in impulsivity. However, other factors, such as elevated testosterone levels, may also be involved. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Mar 2016]

PSMD1 (HGNC:9554): (proteasome 26S subunit, non-ATPase 1) The 26S proteasome is a multicatalytic proteinase complex with a highly ordered structure composed of 2 complexes, a 20S core and a 19S regulator. The 20S core is composed of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. The 19S regulator is composed of a base, which contains 6 ATPase subunits and 2 non-ATPase subunits, and a lid, which contains up to 10 non-ATPase subunits. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. This gene encodes the largest non-ATPase subunit of the 19S regulator lid, which is responsible for substrate recognition and binding. There is evidence that this proteasome and its subunits interact with viral proteins, including those of coronaviruses. Alternatively spliced transcript variants have been found for this gene.[provided by RefSeq, Aug 2020]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.35440397).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HTR2B	NM_000867.5	c.1388C>A	p.Thr463Lys	missense_variant	4/4	ENST00000258400.4
PSMD1	NM_002807.4	c.1883+21394G>T		intron_variant		ENST00000308696.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HTR2B	ENST00000258400.4	c.1388C>A	p.Thr463Lys	missense_variant	4/4	1	NM_000867.5	P1
PSMD1	ENST00000308696.11	c.1883+21394G>T		intron_variant		1	NM_002807.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000798 AC: 2 AN: 250774 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135534

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 SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000883

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461568 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727098

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: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 06, 2021

The c.1388C>A (p.T463K) alteration is located in exon 4 (coding exon 3) of the HTR2B gene. This alteration results from a C to A substitution at nucleotide position 1388, causing the threonine (T) at amino acid position 463 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	0.060
CADD	Benign	23
DANN	Benign	0.97
DEOGEN2	Benign	0.078	T
Eigen	Uncertain	0.43
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.79	T
M_CAP	Benign	0.050	D
MetaRNN	Benign	0.35	T
MetaSVM	Benign	-0.73	T
MutationAssessor	Uncertain	2.0	M
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.66	T
PROVEAN	Benign	-0.41	N
REVEL	Benign	0.22
Sift	Benign	0.26	T
Sift4G	Benign	0.16	T
Polyphen		0.90	P
Vest4		0.41
MutPred		0.39		Gain of ubiquitination at T463 (P = 0.0131);
MVP		0.90
MPC		0.21
ClinPred		0.58	D
GERP RS		5.9
Varity_R		0.52
gMVP		0.76

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: rs150480687; hg19: chr2-231973289;