rs147074020

chr3-49721818-G-A

Variant summary

Our verdict is Benign. Variant got -11 ACMG points: 2P and 13B. PM2 BP4_Strong BP6_Very_Strong BP7

The NM_021971.4(GMPPB):c.1017C>T(p.Asn339=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000209 in 1,613,260 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 Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0010 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00012 (0 hom.)
• Consequence: GMPPB NM_021971.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: -0.424

Genes affected

GMPPB (HGNC:22932): (GDP-mannose pyrophosphorylase B) This gene is thought to encode a GDP-mannose pyrophosphorylase. The encoded protein catalyzes the conversion of mannose-1-phosphate and GTP to GDP-mannose, a reaction involved in the production of N-linked oligosaccharides. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jan 2009]

ACMG classification

Verdict is Benign. Variant got -11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.57).
• BP6: Variant 3-49721818-G-A is Benign according to our data. Variant chr3-49721818-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 391583.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-0.424 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GMPPB	NM_021971.4	c.1017C>T	p.Asn339=	synonymous_variant	9/9	ENST00000308388.7
GMPPB	NM_013334.4	c.1098C>T	p.Asn366=	synonymous_variant	8/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GMPPB	ENST00000308388.7	c.1017C>T	p.Asn339=	synonymous_variant	9/9	1	NM_021971.4	P1

Frequencies

GnomAD3 genomes AF: 0.00101 AC: 154 AN: 152194 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00360

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000267 AC: 67 AN: 250556 Hom.: 0 AF XY: 0.000177 AC XY: 24 AN XY: 135528

Gnomad AFR exome AF: 0.00277

Gnomad AMR exome AF: 0.000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000163

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000440

Gnomad OTH exome AF: 0.000653

GnomAD4 exome AF: 0.000123 AC: 180 AN: 1460948 Hom.: 0 Cov.: 32 AF XY: 0.0000991 AC XY: 72 AN XY: 726870

Gnomad4 AFR exome AF: 0.00412

Gnomad4 AMR exome AF: 0.000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000101

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000144

Gnomad4 OTH exome AF: 0.000166

GnomAD4 genome AF: 0.00103 AC: 157 AN: 152312 Hom.: 0 Cov.: 33 AF XY: 0.000980 AC XY: 73 AN XY: 74464

Gnomad4 AFR AF: 0.00366

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000193

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000662 Hom.: 1

Bravo AF: 0.00122

Asia WGS AF: 0.000577 AC: 2 AN: 3478

EpiCase AF: 0.000109

EpiControl AF: 0.0000593

ClinVar

Significance: Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Aug 09, 2016

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A14;C3809221:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B14;C4518000:Autosomal recessive limb-girdle muscular dystrophy type 2T Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jan 25, 2024

- -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 13, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.57
Cadd	Benign	1.6
Dann	Benign	0.88

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: rs147074020; hg19: chr3-49759251;