rs778418119

Variant names:

• chr9-131522959-C-T
• rs778418119
• NM_001077365.2:c.2031C>T
• POMT1 p.Ser677Ser

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_Strong BP6 BP7

The NM_001077365.2(POMT1):​c.2031C>T​(p.Ser677Ser) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000407 in 1,598,092 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000053 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000039 (0 hom.)
• Consequence: POMT1 NM_001077365.2 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: -0.491
• Publications: 0 publications found

Genes affected

POMT1 (HGNC:9202): (protein O-mannosyltransferase 1) The protein encoded by this gene is an O-mannosyltransferase that requires interaction with the product of the POMT2 gene for enzymatic function. The encoded protein is found in the membrane of the endoplasmic reticulum. Defects in this gene are a cause of Walker-Warburg syndrome (WWS) and limb-girdle muscular dystrophy type 2K (LGMD2K). Several transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Oct 2008]

POMT1 Gene-Disease associations (from GenCC):

• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Genomics England PanelApp, Ambry Genetics, G2P
• myopathy caused by variation in POMT1

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B1

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• autosomal recessive limb-girdle muscular dystrophy type 2K

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy with cerebellar involvement

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy with intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy without intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• muscle-eye-brain disease

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• muscular dystrophy-dystroglycanopathy, type A

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP6: Variant 9-131522959-C-T is Benign according to our data. Variant chr9-131522959-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 499640.
• BP7: Synonymous conserved (PhyloP=-0.491 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001077365.2. 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
	POMT1	NM_001077365.2	MANE Select	c.2031C>T	p.Ser677Ser	synonymous	Exon 20 of 20	NP_001070833.1	A0A140VKE0
	POMT1	NM_001353193.2		c.2097C>T	p.Ser699Ser	synonymous	Exon 20 of 20	NP_001340122.2	Q9Y6A1-1
	POMT1	NM_007171.4		c.2097C>T	p.Ser699Ser	synonymous	Exon 20 of 20	NP_009102.4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POMT1	ENST00000402686.8	TSL:1 MANE Select	c.2031C>T	p.Ser677Ser	synonymous	Exon 20 of 20	ENSP00000385797.4	Q9Y6A1-2
	POMT1	ENST00000372228.9	TSL:1	c.2097C>T	p.Ser699Ser	synonymous	Exon 20 of 20	ENSP00000361302.3	Q9Y6A1-1
	POMT1	ENST00000423007.6	TSL:1	c.2088C>T	p.Ser696Ser	synonymous	Exon 19 of 19	ENSP00000404119.2	A0A1V1FTP4

Frequencies

GnomAD3 genomes AF: 0.0000526 AC: 8 AN: 152186 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000327

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.000478

GnomAD2 exomes AF: 0.0000348 AC: 8 AN: 229920 AF XY: 0.0000241

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000675

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000394 AC: 57 AN: 1445906 Hom.: 0 Cov.: 34 AF XY: 0.0000362 AC XY: 26 AN XY: 718194

African (AFR) AF: 0.0000301 AC: 1 AN: 33254

American (AMR) AF: 0.0000928 AC: 4 AN: 43088

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25802

East Asian (EAS) AF: 0.00 AC: 0 AN: 39464

South Asian (SAS) AF: 0.0000948 AC: 8 AN: 84426

European-Finnish (FIN) AF: 0.0000202 AC: 1 AN: 49594

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4146

European-Non Finnish (NFE) AF: 0.0000371 AC: 41 AN: 1106306

Other (OTH) AF: 0.0000334 AC: 2 AN: 59826

GnomAD4 genome AF: 0.0000526 AC: 8 AN: 152186 Hom.: 0 Cov.: 33 AF XY: 0.0000404 AC XY: 3 AN XY: 74338

African (AFR) AF: 0.00 AC: 0 AN: 41442

American (AMR) AF: 0.000327 AC: 5 AN: 15278

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68030

Other (OTH) AF: 0.000478 AC: 1 AN: 2094

Alfa AF: 0.0000457 Hom.: 0

Bravo AF: 0.0000982

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	1	not provided (2)
-	-	1	Walker-Warburg congenital muscular dystrophy;C1836373:Autosomal recessive limb-girdle muscular dystrophy type 2K;C5436962:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
CADD	Benign	0.19
DANN	Benign	0.83
PhyloP100		-0.49
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs778418119;

hg19: chr9-134398346;