1-26432313-G-A

Variant summary

Our verdict is Benign. Variant got -12 ACMG points: 0P and 12B. BP4_Moderate BP6_Moderate BS1 BS2

The ENST00000434391.6(DHDDS):c.-119G>A variant causes a 5 prime UTR, NMD transcript change. The variant allele was found at a frequency of 0.00999 in 152,330 control chromosomes in the GnomAD database, including 32 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.010 (32 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: DHDDS ENST00000434391.6 5_prime_UTR, NMD_transcript
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 4.54

Genes affected

DHDDS (HGNC:20603): (dehydrodolichyl diphosphate synthase subunit) The protein encoded by this gene catalyzes cis-prenyl chain elongation to produce the polyprenyl backbone of dolichol, a glycosyl carrier lipid required for the biosynthesis of several classes of glycoproteins. Mutations in this gene are associated with retinitis pigmentosa type 59. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Aug 2011]

ACMG classification

Verdict is Benign. Variant got -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.24).
• BP6: Variant 1-26432313-G-A is Benign according to our data. Variant chr1-26432313-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 297070.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00999 (1522/152330) while in subpopulation AFR AF= 0.0347 (1443/41572). AF 95% confidence interval is 0.0332. There are 32 homozygotes in gnomad4. There are 713 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd at 32 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DHDDS	NM_205861.3			upstream_gene_variant		ENST00000236342.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DHDDS	ENST00000236342.12			upstream_gene_variant		1	NM_205861.3	P4

Frequencies

GnomAD3 genomes AF: 0.00999 AC: 1521 AN: 152212 Hom.: 32 Cov.: 32

Gnomad AFR AF: 0.0348

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00386

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.0000735

Gnomad OTH AF: 0.00621

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 798 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 506

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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 AF: 0.00999 AC: 1522 AN: 152330 Hom.: 32 Cov.: 32 AF XY: 0.00957 AC XY: 713 AN XY: 74504

Gnomad4 AFR AF: 0.0347

Gnomad4 AMR AF: 0.00386

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000735

Gnomad4 OTH AF: 0.00615

Alfa AF: 0.00218 Hom.: 1

Bravo AF: 0.0116

Asia WGS AF: 0.00144 AC: 5 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Retinitis pigmentosa Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 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 and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.24
Cadd	Benign	22
Dann	Benign	0.96

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs115681222; hg19: chr1-26758804;