NM_001297436.2:c.1240G>T

Variant names:

• chr19-51713921-C-A
• rs45625331
• NM_001297436.2:c.1240G>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001297436.2(HAS1):​c.1240G>T​(p.Val414Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,456,048 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign 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. V414M) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: HAS1 NM_001297436.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.42
• Publications: 0 publications found

Genes affected

HAS1 (HGNC:4818): (hyaluronan synthase 1) Hyaluronan or hyaluronic acid (HA) is a high molecular weight unbranched polysaccharide synthesized by a wide variety of organisms from bacteria to mammals, and is a constituent of the extracellular matrix. It consists of alternating glucuronic acid and N-acetylglucosamine residues that are linked by beta-1-3 and beta-1-4 glycosidic bonds. HA is synthesized by membrane-bound synthase at the inner surface of the plasma membrane, and the chains are extruded through pore-like structures into the extracellular space. It serves a variety of functions, including space filling, lubrication of joints, and provision of a matrix through which cells can migrate. HA is actively produced during wound healing and tissue repair to provide a framework for ingrowth of blood vessels and fibroblasts. Changes in the serum concentration of HA are associated with inflammatory and degenerative arthropathies such as rheumatoid arthritis. In addition, the interaction of HA with the leukocyte receptor CD44 is important in tissue-specific homing by leukocytes, and overexpression of HA receptors has been correlated with tumor metastasis. HAS1 is a member of the newly identified vertebrate gene family encoding putative hyaluronan synthases, and its amino acid sequence shows significant homology to the hasA gene product of Streptococcus pyogenes, a glycosaminoglycan synthetase (DG42) from Xenopus laevis, and a recently described murine hyaluronan synthase. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014]

ACMG classification

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 (MetaRNN=0.16163152).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001297436.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HAS1	NM_001297436.2	MANE Select	c.1240G>T	p.Val414Leu	missense	Exon 5 of 5	NP_001284365.1	G3V1S7
	HAS1	NM_001523.4		c.1243G>T	p.Val415Leu	missense	Exon 5 of 5	NP_001514.2	Q92839

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HAS1	ENST00000540069.7	TSL:1 MANE Select	c.1240G>T	p.Val414Leu	missense	Exon 5 of 5	ENSP00000445021.2	G3V1S7
	HAS1	ENST00000601714.5	TSL:1	c.1264G>T	p.Val422Leu	missense	Exon 4 of 4	ENSP00000472821.1	M0R2V0
	HAS1	ENST00000222115.5	TSL:1	c.1243G>T	p.Val415Leu	missense	Exon 5 of 5	ENSP00000222115.1	Q92839

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1456048 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 724568

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 47680

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111960

Other (OTH) AF: 0.00 AC: 0 AN: 60364

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.54
BayesDel_addAF	Benign	-0.033	T
BayesDel_noAF	Benign	-0.29
CADD	Benign	20
DANN	Benign	0.83
DEOGEN2	Benign	0.11	T
Eigen	Benign	-0.58
Eigen_PC	Benign	-0.45
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Benign	0.84	T
M_CAP	Benign	0.032	D
MetaRNN	Benign	0.16	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.34	N
PhyloP100		3.4
PrimateAI	Pathogenic	0.91	D
PROVEAN	Benign	-0.55	N
REVEL	Benign	0.24
Sift	Benign	1.0	T
Sift4G	Benign	0.61	T
Polyphen		0.084	B
Vest4		0.13
MutPred		0.64		Loss of catalytic residue at V415 (P = 0.0042)
MVP		0.50
MPC		0.078
ClinPred		0.58	D
GERP RS		3.2
Varity_R		0.13
gMVP		0.46
Mutation Taster		=66/34	polymorphism

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

Other links and lift over

dbSNP: rs45625331; hg19: chr19-52217174;