NM_001256007.3:c.634_637delAATT

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate

The NM_001256007.3(PNPLA8):​c.634_637delAATT​(p.Asn212HisfsTer29) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000248 in 1,610,122 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

PNPLA8
NM_001256007.3 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, single submitter P:2

Conservation

PhyloP100: 6.68

Publications

3 publications found
Variant links:
Genes affected
PNPLA8 (HGNC:28900): (patatin like phospholipase domain containing 8) This gene encodes a member of the patatin-like phospholipase domain containing protein family. Members of this family are phospholipases which catalyze the cleavage of fatty acids from membrane phospholipids. The product of this gene is a calcium-independent phospholipase. Mutations in this gene have been associated with mitochondrial myopathy with lactic acidosis. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2015]
PNPLA8 Gene-Disease associations (from GenCC):
  • mitochondrial myopathy-lactic acidosis-deafness syndrome
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 7-108514854-GAATT-G is Pathogenic according to our data. Variant chr7-108514854-GAATT-G is described in ClinVar as Pathogenic. ClinVar VariationId is 190127.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PNPLA8NM_001256007.3 linkc.634_637delAATT p.Asn212HisfsTer29 frameshift_variant Exon 3 of 11 ENST00000257694.13 NP_001242936.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PNPLA8ENST00000257694.13 linkc.634_637delAATT p.Asn212HisfsTer29 frameshift_variant Exon 3 of 11 1 NM_001256007.3 ENSP00000257694.8

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152146
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
GnomAD4 exome
AF:
0.00000206
AC:
3
AN:
1457976
Hom.:
0
AF XY:
0.00000138
AC XY:
1
AN XY:
725616
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000900
AC:
3
AN:
33330
American (AMR)
AF:
0.00
AC:
0
AN:
44516
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26086
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86014
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53328
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5754
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1109028
Other (OTH)
AF:
0.00
AC:
0
AN:
60248
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00131091), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.392
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152146
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74326
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41438
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10594
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Mitochondrial myopathy-lactic acidosis-deafness syndrome Pathogenic:1
Mar 01, 2015
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

not provided Pathogenic:1
Dec 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Asn212Hisfs*29) in the PNPLA8 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PNPLA8 are known to be pathogenic (PMID: 29681094). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with clinical features of mitochondrial myopathy with lactic acidosis (PMID: 25512002). This variant is also known as c.334_337delAATT (p.Asn112HisfsX29). ClinVar contains an entry for this variant (Variation ID: 190127). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
6.7
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs786205882; hg19: chr7-108155298; API