20-50934884-A-T

Position:

• chr20-50934884-A-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The NM_003859.3(DPM1):​c.*248T>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000333 in 303,702 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 Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00027 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00040 (0 hom.)
• Consequence: DPM1 NM_003859.3 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -3.12

Genes affected

DPM1 (HGNC:3005): (dolichyl-phosphate mannosyltransferase subunit 1, catalytic) Dolichol-phosphate mannose (Dol-P-Man) serves as a donor of mannosyl residues on the lumenal side of the endoplasmic reticulum (ER). Lack of Dol-P-Man results in defective surface expression of GPI-anchored proteins. Dol-P-Man is synthesized from GDP-mannose and dolichol-phosphate on the cytosolic side of the ER by the enzyme dolichyl-phosphate mannosyltransferase. Human DPM1 lacks a carboxy-terminal transmembrane domain and signal sequence and is regulated by DPM2. Mutations in this gene are associated with congenital disorder of glycosylation type Ie. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2015]

ADNP-AS1 (HGNC:51227): (ADNP antisense RNA 1)

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.96).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.000269 (41/152206) while in subpopulation NFE AF= 0.000456 (31/68016). AF 95% confidence interval is 0.00033. There are 0 homozygotes in gnomad4. There are 16 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DPM1	NM_003859.3	c.*248T>A		3_prime_UTR_variant	9/9	ENST00000371588.10
ADNP-AS1	NR_110008.1	n.149+3435A>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DPM1	ENST00000371588.10	c.*248T>A		3_prime_UTR_variant	9/9	1	NM_003859.3	P1
ADNP-AS1	ENST00000558899.2	n.149+3435A>T		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes AF: 0.000269 AC: 41 AN: 152206 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000659

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000456

Gnomad OTH AF: 0.000479

GnomAD4 exome AF: 0.000396 AC: 60 AN: 151496 Hom.: 0 Cov.: 0 AF XY: 0.000452 AC XY: 36 AN XY: 79624

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.000208

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.000103

Gnomad4 NFE exome AF: 0.000592

Gnomad4 OTH exome AF: 0.000217

GnomAD4 genome AF: 0.000269 AC: 41 AN: 152206 Hom.: 0 Cov.: 33 AF XY: 0.000215 AC XY: 16 AN XY: 74354

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.000659

Gnomad4 NFE AF: 0.000456

Gnomad4 OTH AF: 0.000479

Alfa AF: 0.000688 Hom.: 0

Bravo AF: 0.000181

Asia WGS AF: 0.00116 AC: 4 AN: 3464

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital disorder of glycosylation type 1E Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.96
CADD	Benign	0.067
DANN	Benign	0.30
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.1

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: rs1020154329; hg19: chr20-49551421;