17-10391974-C-G

Position:

• chr17-10391974-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP2 PP3

The NM_002472.3(MYH8):​c.5572G>C​(p.Glu1858Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,434 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MYH8 NM_002472.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.86

Genes affected

MYH8 (HGNC:7578): (myosin heavy chain 8) Myosins are actin-based motor proteins that function in the generation of mechanical force in eukaryotic cells. Muscle myosins are heterohexamers composed of 2 myosin heavy chains and 2 pairs of nonidentical myosin light chains. This gene encodes a member of the class II or conventional myosin heavy chains, and functions in skeletal muscle contraction. This gene is predominantly expressed in fetal skeletal muscle. This gene is found in a cluster of myosin heavy chain genes on chromosome 17. A mutation in this gene results in trismus-pseudocamptodactyly syndrome. [provided by RefSeq, Sep 2009]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), MYH8. . Gene score misZ 0.34953 (greater than the threshold 3.09). Trascript score misZ 3.2125 (greater than threshold 3.09). GenCC has associacion of gene with trismus-pseudocamptodactyly syndrome, Carney complex - trismus - pseudocamptodactyly syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.798

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYH8	NM_002472.3	c.5572G>C	p.Glu1858Gln	missense_variant	39/40	ENST00000403437.2	NP_002463.2
MYHAS	NR_125367.1	n.76+8767C>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYH8	ENST00000403437.2	c.5572G>C	p.Glu1858Gln	missense_variant	39/40	5	NM_002472.3	ENSP00000384330	P1
	ENST00000399342.6	n.76+8767C>G		intron_variant, non_coding_transcript_variant		3
	ENST00000581304.1	n.52+8767C>G		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461434 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727058

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.0000113

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

Nov 21, 2022

The c.5572G>C (p.E1858Q) alteration is located in exon 39 (coding exon 37) of the MYH8 gene. This alteration results from a G to C substitution at nucleotide position 5572, causing the glutamic acid (E) at amino acid position 1858 to be replaced by a glutamine (Q). 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	Uncertain	0.38
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.0
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.37	T
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.93	D
M_CAP	Benign	0.041	D
MetaRNN	Pathogenic	0.80	D
MetaSVM	Uncertain	0.46	D
MutationAssessor	Pathogenic	4.3	H
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.71	T
PROVEAN	Benign	-1.7	N
REVEL	Pathogenic	0.71
Sift	Uncertain	0.010	D
Sift4G	Uncertain	0.0080	D
Polyphen		0.48	P
Vest4		0.71
MutPred		0.67		Gain of MoRF binding (P = 0.025);
MVP		0.87
MPC		0.55
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.24
gMVP		0.43

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: rs2072029597; hg19: chr17-10295291;