rs118161496

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP3BS2

The NM_025152.3(NUBPL):​c.815-27T>C variant causes a intron change. The variant allele was found at a frequency of 0.00373 in 1,571,878 control chromosomes in the GnomAD database, including 22 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). There are indicators that this mutation may affect the branch point..

Frequency

Genomes: 𝑓 0.0034 ( 3 hom., cov: 32)
Exomes 𝑓: 0.0038 ( 19 hom. )

Consequence

NUBPL
NM_025152.3 intron

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:8U:5

Conservation

PhyloP100: 3.77
Variant links:
Genes affected
NUBPL (HGNC:20278): (NUBP iron-sulfur cluster assembly factor, mitochondrial) This gene encodes a member of the Mrp/NBP35 ATP-binding proteins family. The encoded protein is required for the assembly of the respiratory chain NADH dehydrogenase (complex I), an oligomeric enzymatic complex located in the inner mitochondrial membrane. Mutations in this gene cause mitochondrial complex I deficiency. Alternative splicing results in multiple transcript variants. [provided by RefSeq, May 2014]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
BS2
High Homozygotes in GnomAd4 at 3 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
NUBPLNM_025152.3 linkuse as main transcriptc.815-27T>C intron_variant ENST00000281081.12 NP_079428.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
NUBPLENST00000281081.12 linkuse as main transcriptc.815-27T>C intron_variant 1 NM_025152.3 ENSP00000281081 P1Q8TB37-1

Frequencies

GnomAD3 genomes
AF:
0.00340
AC:
517
AN:
152256
Hom.:
3
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000579
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00131
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00145
Gnomad FIN
AF:
0.0149
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.00444
Gnomad OTH
AF:
0.00191
GnomAD3 exomes
AF:
0.00345
AC:
857
AN:
248676
Hom.:
10
AF XY:
0.00349
AC XY:
471
AN XY:
134910
show subpopulations
Gnomad AFR exome
AF:
0.000777
Gnomad AMR exome
AF:
0.000726
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.000950
Gnomad FIN exome
AF:
0.0122
Gnomad NFE exome
AF:
0.00442
Gnomad OTH exome
AF:
0.00513
GnomAD4 exome
AF:
0.00377
AC:
5351
AN:
1419504
Hom.:
19
Cov.:
25
AF XY:
0.00373
AC XY:
2645
AN XY:
709074
show subpopulations
Gnomad4 AFR exome
AF:
0.000459
Gnomad4 AMR exome
AF:
0.000806
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00108
Gnomad4 FIN exome
AF:
0.0124
Gnomad4 NFE exome
AF:
0.00407
Gnomad4 OTH exome
AF:
0.00286
GnomAD4 genome
AF:
0.00339
AC:
516
AN:
152374
Hom.:
3
Cov.:
32
AF XY:
0.00364
AC XY:
271
AN XY:
74508
show subpopulations
Gnomad4 AFR
AF:
0.000577
Gnomad4 AMR
AF:
0.00131
Gnomad4 ASJ
AF:
0.000288
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00145
Gnomad4 FIN
AF:
0.0149
Gnomad4 NFE
AF:
0.00442
Gnomad4 OTH
AF:
0.00189
Alfa
AF:
0.00323
Hom.:
0
Bravo
AF:
0.00228
Asia WGS
AF:
0.000289
AC:
1
AN:
3476

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:8Uncertain:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Mitochondrial complex 1 deficiency, nuclear type 21 Pathogenic:5Uncertain:2
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJul 07, 2023Variant summary: NUBPL c.815-27T>C is located at a position not widely known to affect splicing. 4/4 computational tools predict no significant impact on normal splicing. However, at least two publications report experimental evidence that this variant affects mRNA splicing (Tucker_2012, Kimonis_2021). The variant allele was found at a frequency of 0.0034 in 248676 control chromosomes in the gnomAD database, including 10 homozygotes. c.815-27T>C has been reported in the literature in multiple individuals affected with Mitochondrial Complex 1 Deficiency, Nuclear Type 21 (Calvo_2010, Kevelam_2013, Kimonis_2021), and some were reported as compound heterozygous with other (likely) pathogenic variants. These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein expression, finding that a heterozygous control with the variant exhibited far lower expression of NUBPL protein (Tucker_2012). The following publications have been ascertained in the context of this evaluation (PMID: 20818383, 23553477, 22072591, 32518176). 11 submitters have cited clinical-significance assessments for this variant to ClinVar after 2014, and classified it as pathogenic/likely pathogenic (n=8) or uncertain significance (n=3). Based on the evidence outlined above, the variant was classified as pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingInstitute for Genomic Medicine (IGM) Clinical Laboratory, Nationwide Children's HospitalJun 15, 2018[ACMG/AMP: PS3, PP3, PP5, BS1] This alteration is supported by well-established in vitro or in vivo functional studies to have a damaging effect on protein function or splicing [PS3], is predicted to be damaging by multiple functional prediction tools [PP3], was reported as a pathogenic/likely pathogenic alteration by a reputable source (ClinVar or other correspondence from a clinical testing laboratory) [PP5], has an allele frequency that is greater than expected for the associated disease [BS1]. -
Likely pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvityJan 08, 2024- -
Uncertain significance, criteria provided, single submitterclinical testingVictorian Clinical Genetics Services, Murdoch Childrens Research InstituteOct 19, 2020Based on the classification scheme VCGS_Germline_v1.1.1, this variant is classified as 3B-VUS. Following criteria are met: 0102 - Loss-of-function is a known mechanism of disease for this gene. (N) 0106 - This gene is known to be associated with autosomal recessive disease. (N) 0210 - Splice site variant (canonical or non-canonical) proven to affect splicing/expression of the transcript with a known effect on protein structure. Functional studies showed three alternate transcripts were generated as a result of aberrant splicing from the allele with this variant: one transcript with normal splicing, one with exon 10 skipped resulting in a frameshift but no nonsense-mediated decay (NMD), and a third transcript that utilised a cryptic splice site resulting in a frameshift and NMD (PMIDs: 22072591, 32518176). (P) 0251 - Variant is heterozygous. (N) 0305 - Variant is present in gnomAD >=0.01 and <0.03 for a recessive condition (972 heterozygotes, 10 homozygotes). (N) 0705 - No comparable variants have previous evidence for pathogenicity. (N) 0803 - Low previous evidence of pathogenicity in unrelated individuals. An allele harbouring this variant in cis with a second variant (p.(Gly56Arg)) has been reported as pathogenic in many patients, majority of whom were in compound heterozygous state with a pathogenic allele (PMIDs: 22072591, 25245479, 23553477). However, an allele harbouring this variant without the p.(Gly56Arg) variant has been associated with disease in one family (PMID: 32518176). (P) 1001 - Strong functional evidence supporting abnormal protein function. Functional studies showed levels of NUBPL mRNA and protein were decreased in the fibroblast cells heterozygous for this variant alone (PMID: 22072591). (P) 1205 - Variant is maternally inherited. (N) Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -
Pathogenic, no assertion criteria providedliterature onlyOMIMJul 20, 2021- -
Uncertain significance, criteria provided, single submitterclinical testingUndiagnosed Diseases Network, NIHAug 24, 2020- -
Pathogenic, criteria provided, single submitterclinical testingMendelicsMay 04, 2022- -
not provided Pathogenic:1Uncertain:2
Pathogenic, criteria provided, single submitterclinical testingGeneDxAug 14, 2017Expression studies of the c.815-27 T>C sequence change found that this variant impairs mRNA splicing resulting in a 80% decrease in complex I assembly and function (Tucker et al., 2012; Wydro et al., 2013). Therefore, based on the currently available information, the c.815-27 T>C variant is a strong candidate for a pathogenic variant; however, the possibility that it is a benign variant cannot be excluded. -
Uncertain significance, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenFeb 01, 2023NUBPL: PM3:Strong, PS3:Moderate, PM2:Supporting, PP3, BS2 -
Uncertain significance, criteria provided, single submitterclinical testingCenter for Pediatric Genomic Medicine, Children's Mercy Hospital and ClinicsJan 09, 2017- -
Mitochondrial complex I deficiency Pathogenic:1Uncertain:1
Likely pathogenic, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicMay 01, 2017- -
Uncertain significance, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineFeb 16, 2024The c.815-27T>C variant in NUBPL is typically observed as a compound allele (in cis) with the c.166G>A [p.G56R] variant in individuals with mitochondrial complex I deficiency. By itself, it has been reported in at least one individual with mitochondrial complex I deficiency and an another variant in trans, and segregated with disease in at least 1 sibling (Kimonis 2021 PMID: 32518176; Maclean 2018 PMID:29982452). This variant has also been identified in 1.28% (819/63974) of European (Finnish) chromosomes, including 22 homozygotes, by gnomAD (http://gnomad.broadinstitute.org, v4.0.0) and reported in ClinVar (Variation ID 50317). This variant is located in the splice branch site, and computational prediction tools suggest an impact on splicing. An RT-PCR study demonstrated that this variant results in three transcripts: wild-type, the use of a cryptic acceptor site (p.G272VfsX11), or skipping of exon 10 (p.D273QfsX31). In addition, in vitro functional studies demonstrated that patient cells express reduced levels of the wild-type transcript, possibly as a result of degradation of a variant transcript by NMD (Tucker 2012 PMID: 22072591). Overall, it is unclear if this variant in isolation causes disease or whether it acts in synergy with the p.G56R variant. Therefore, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PM3, PP1, PP3, PS3_Supporting, BS1_Supporting. -
Inborn genetic diseases Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsApr 13, 2021The c.815-27T>C intronic alteration consists of a T to C substitution 27 nucleotides before coding exon 10 in the NUBPL gene and is predicted to affect the native branch site. Based on data from the Genome Aggregation Database (gnomAD) database, the NUBPL c.815-27T>C alteration was observed in 0.35% (992/280082) of total alleles studied (including 10 homozygotes), with a frequency of 1.24% (310/24978) in the European (Finnish) subpopulation. The [c.166G>A (p.G56R); c.815-27T>C] complex allele has been reported in the homozygous state, compound heterozygous state, and confirmed in trans with a second pathogenic allele in multiple unrelated patients with mitochondrial encephalomyopathy (Calvo, 2010; Kevelam, 2013). Emerging evidence is suggestive that the NUBPL [c.166G>A (p.G56R); c.815-27T>C] complex allele is likely pathogenic when these alterations are in cis; however, the clinical significance of these alterations in isolation remains uncertain. The c.815-27T nucleotide is highly conserved in available vertebrate species. Functional analysis of cultured fibroblasts from a patient bearing the [c.166G>A (p.G56R); c.815-27T>C] complex allele in trans with a complex rearrangement, as well as a control patient who was heterozygous for only the c.815-27T>C alteration, demonstrated an aberrant RT-PCR pattern with three distinct transcripts: wild-type, a lengthened transcript resulting from a cryptic splice site which introduces an additional 72 bp and results in a frameshift (p.G272Vfs*11), as well as a truncated transcript generated due to exon 10 skipping resulting in a frameshift (p.D273Qfs*31) (Tucker, 2012). Analysis by qRT-PCR and Western blot showed that the heterozygous control with only the c.815-27T>C alteration had reduced mRNA expression (74%) and protein expression (59%) compared to wild type controls, and the patient with the [c.166G>A (p.G56R); c.815-27T>C] complex allele and complex rearrangement on the other allele had more significant reduction in mRNA expression (15%) and undetectable protein expression (Tucker, 2012). No defective function was identified when the protein with the G56R missense change was over-expressed (Tucker, 2012). The p.D273Qfs*31 transcript is completely non-functional in yeast assays (Wydro, 2013; Maclean, 2018). In silico splice site analysis predicts that the c.815-27T>C alteration will weaken the native splice acceptor site and will result in the creation or strengthening of a novel splice acceptor site. Based on the available evidence, this alteration is classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.79
CADD
Benign
22
DANN
Benign
0.68
BranchPoint Hunter
6.0

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.71
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.70
Position offset: -45
DS_AL_spliceai
0.71
Position offset: 27

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs118161496; hg19: chr14-32319298; API