rs768892122

Variant names:

• chr2-55636255-T-C
• rs768892122
• NM_033109.5:c.2334A>G

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 0P and 11B. BP4_Strong BP6_Moderate BP7 BS1

The NM_033109.5(PNPT1):​c.2334A>G​(p.Ser778Ser) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,611,226 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 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: PNPT1 NM_033109.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.0270
• Publications: 0 publications found

Genes affected

PNPT1 (HGNC:23166): (polyribonucleotide nucleotidyltransferase 1) The protein encoded by this gene belongs to the evolutionary conserved polynucleotide phosphorylase family comprised of phosphate dependent 3'-to-5' exoribonucleases implicated in RNA processing and degradation. This enzyme is predominantly localized in the mitochondrial intermembrane space and is involved in import of RNA to mitochondria. Mutations in this gene have been associated with combined oxidative phosphorylation deficiency-13 and autosomal recessive nonsyndromic deafness-70. Related pseudogenes are found on chromosomes 3 and 7. [provided by RefSeq, Dec 2012]

PNPT1 Gene-Disease associations (from GenCC):

• combined oxidative phosphorylation defect type 13

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia
• hearing loss disorder

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• Leigh syndrome

  Inheritance: AR Classification: MODERATE Submitted by: ClinGen
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• spinocerebellar ataxia type 25

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• autosomal recessive nonsyndromic hearing loss 70

  Inheritance: AR, Unknown Classification: LIMITED Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Benign. The variant received -11 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.47).
• BP6: Variant 2-55636255-T-C is Benign according to our data. Variant chr2-55636255-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 2872434.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.027 with no splicing effect.
• BS1: Variant frequency is greater than expected in population mid. GnomAdExome4 allele frequency = 0.000011 (16/1459150) while in subpopulation MID AF = 0.00191 (11/5748). AF 95% confidence interval is 0.00107. There are 0 homozygotes in GnomAdExome4. There are 8 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_033109.5. 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
	PNPT1	NM_033109.5	MANE Select	c.2334A>G	p.Ser778Ser	synonymous	Exon 28 of 28	NP_149100.2	Q8TCS8

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PNPT1	ENST00000447944.7	TSL:1 MANE Select	c.2334A>G	p.Ser778Ser	synonymous	Exon 28 of 28	ENSP00000400646.2	Q8TCS8
	PNPT1	ENST00000917025.1		c.2352A>G	p.Ser784Ser	synonymous	Exon 28 of 28	ENSP00000587084.1
	PNPT1	ENST00000867135.1		c.2331A>G	p.Ser777Ser	synonymous	Exon 28 of 28	ENSP00000537194.1

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 152076 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.000956

GnomAD2 exomes AF: 0.0000240 AC: 6 AN: 249548 AF XY: 0.0000371

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: 0.00

Gnomad OTH exome AF: 0.000985

GnomAD4 exome AF: 0.0000110 AC: 16 AN: 1459150 Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8 AN XY: 725636

African (AFR) AF: 0.00 AC: 0 AN: 33420

American (AMR) AF: 0.00 AC: 0 AN: 44556

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26094

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00 AC: 0 AN: 85546

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53350

Middle Eastern (MID) AF: 0.00191 AC: 11 AN: 5748

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1110450

Other (OTH) AF: 0.0000497 AC: 3 AN: 60306

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 152076 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74276

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41396

American (AMR) AF: 0.00 AC: 0 AN: 15266

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10564

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68028

Other (OTH) AF: 0.000956 AC: 2 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.00000000770867), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.000305 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions as Germline

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.47
CADD	Benign	8.3
DANN	Benign	0.72
PhyloP100		0.027
Mutation Taster		=100/0	polymorphism

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

Other links and lift over

dbSNP: rs768892122; hg19: chr2-55863390;