9-133514737-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_001080483.3(MYMK):c.565A>G(p.Met189Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,754 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: MYMK NM_001080483.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.53

Genes affected

MYMK (HGNC:33778): (myomaker, myoblast fusion factor) Involved in myoblast fusion. Located in plasma membrane. Implicated in Carey-Fineman-Ziter syndrome. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a chain Protein myomaker (size 220) in uniprot entity MYMK_HUMAN there are 10 pathogenic changes around while only 1 benign (91%) in NM_001080483.3
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18616527).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYMK	NM_001080483.3	c.565A>G	p.Met189Val	missense_variant	5/5	ENST00000339996.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYMK	ENST00000339996.4	c.565A>G	p.Met189Val	missense_variant	5/5	2	NM_001080483.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251314 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135828

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000109

Gnomad SAS 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: 0.00000205 AC: 3 AN: 1461754 Hom.: 0 Cov.: 29 AF XY: 0.00000275 AC XY: 2 AN XY: 727202

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 17, 2023

The c.565A>G (p.M189V) alteration is located in exon 5 (coding exon 5) of the TMEM8C gene. This alteration results from a A to G substitution at nucleotide position 565, causing the methionine (M) at amino acid position 189 to be replaced by a valine (V). 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	0.067
BayesDel_addAF	Benign	-0.36	T
BayesDel_noAF	Benign	-0.53
Cadd	Benign	13
Dann	Benign	0.86
DEOGEN2	Benign	0.025	T
Eigen	Benign	-0.41
Eigen_PC	Benign	-0.32
FATHMM_MKL	Benign	0.71	D
LIST_S2	Benign	0.79	T
M_CAP	Benign	0.025	T
MetaRNN	Benign	0.19	T
MetaSVM	Benign	-1.1	T
MutationTaster	Benign	0.99	D
PrimateAI	Uncertain	0.50	T
PROVEAN	Benign	-0.45	N
REVEL	Benign	0.055
Sift	Benign	0.25	T
Sift4G	Benign	0.16	T
Polyphen		0.0020	B
Vest4		0.26
MutPred		0.53		Gain of catalytic residue at M189 (P = 0.0118);
MVP		0.13
MPC		0.33
ClinPred		0.081	T
GERP RS		2.6
Varity_R		0.13
gMVP		0.41

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs1174581902; hg19: chr9-136379859; COSMIC: COSV60600093; COSMIC: COSV60600093;