chr17-47209490-C-T

Variant names:

• chr17-47209490-C-T
• rs764371297
• NM_002476.2:c.68C>T

Variant summary

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

The NM_002476.2(MYL4):​c.68C>T​(p.Pro23Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,882 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. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P23R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYL4 NM_002476.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.37
• Publications: 0 publications found

Genes affected

MYL4 (HGNC:7585): (myosin light chain 4) Myosin is a hexameric ATPase cellular motor protein. It is composed of two myosin heavy chains, two nonphosphorylatable myosin alkali light chains, and two phosphorylatable myosin regulatory light chains. This gene encodes a myosin alkali light chain that is found in embryonic muscle and adult atria. Two alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2008]

MYL4 Gene-Disease associations (from GenCC):

• atrial fibrillation, familial, 18

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• familial atrial fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

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=0.16154164).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYL4	NM_002476.2	c.68C>T	p.Pro23Leu	missense_variant	Exon 1 of 7	ENST00000393450.5	NP_002467.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYL4	ENST00000393450.5	c.68C>T	p.Pro23Leu	missense_variant	Exon 1 of 7	1	NM_002476.2	ENSP00000377096.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251362 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.00000137 AC: 2 AN: 1461882 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.0000447 AC: 2 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Atrial fibrillation, familial, 18 Uncertain:1

Oct 07, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This variant has not been reported in the literature in individuals with MYL4-related conditions. This sequence change replaces proline with leucine at codon 23 of the MYL4 protein (p.Pro23Leu). The proline residue is weakly conserved and there is a moderate physicochemical difference between proline and leucine. This variant is not present in population databases (ExAC no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Benign	-0.044	T
BayesDel_noAF	Benign	-0.22
CADD	Benign	20
DANN	Benign	0.80
DEOGEN2	Benign	0.42	T;T;T;.;T;T
Eigen	Benign	-0.51
Eigen_PC	Benign	-0.58
FATHMM_MKL	Benign	0.39	N
LIST_S2	Benign	0.83	.;T;T;T;.;T
M_CAP	Benign	0.010	T
MetaRNN	Benign	0.16	T;T;T;T;T;T
MetaSVM	Uncertain	-0.091	T
MutationAssessor	Uncertain	2.1	M;M;.;.;M;.
PhyloP100		1.4
PrimateAI	Uncertain	0.55	T
PROVEAN	Benign	-1.6	.;N;.;.;N;.
REVEL	Benign	0.22
Sift	Benign	0.13	.;T;.;.;T;.
Sift4G	Uncertain	0.0040	D;D;D;D;D;D
Polyphen		0.15	B;B;.;.;B;.
Vest4		0.34
MutPred		0.25		Loss of glycosylation at P23 (P = 0.0035);Loss of glycosylation at P23 (P = 0.0035);Loss of glycosylation at P23 (P = 0.0035);Loss of glycosylation at P23 (P = 0.0035);Loss of glycosylation at P23 (P = 0.0035);Loss of glycosylation at P23 (P = 0.0035);
MVP		0.74
MPC		0.15
ClinPred		0.11	T
GERP RS		3.7
PromoterAI		0.0088	Neutral
Varity_R		0.054
gMVP		0.41

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: rs764371297; hg19: chr17-45286856;