rs199504211

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PP2PP5BS1_Supporting

The NM_018082.6(POLR3B):​c.1244T>C​(p.Met415Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000871 in 1,613,792 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00064 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00089 ( 1 hom. )

Consequence

POLR3B
NM_018082.6 missense

Scores

6
10
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:9U:9O:1

Conservation

PhyloP100: 7.52
Variant links:
Genes affected
POLR3B (HGNC:30348): (RNA polymerase III subunit B) This gene encodes the second largest subunit of RNA polymerase III, the polymerase responsible for synthesizing transfer and small ribosomal RNAs in eukaryotes. The largest subunit and the encoded protein form the catalytic center of RNA polymerase III. Mutations in this gene are a cause of hypomyelinating leukodystrophy. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2011]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PP2
Missense variant in the POLR3B gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 24 curated pathogenic missense variants (we use a threshold of 10). The gene has 6 curated benign missense variants. Gene score misZ: 3.1978 (above the threshold of 3.09). Trascript score misZ: 3.4842 (above the threshold of 3.09). GenCC associations: The gene is linked to hypomyelination-hypogonadotropic hypogonadism-hypodontia syndrome, Charcot-Marie-Tooth disease, demyelinating, IIA 1I, hypomyelinating leukodystrophy 8 with or without oligodontia and-or hypogonadotropic hypogonadism, endosteal sclerosis-cerebellar hypoplasia syndrome.
PP5
Variant 12-106427339-T-C is Pathogenic according to our data. Variant chr12-106427339-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 285205.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=5, Uncertain_significance=8, Pathogenic=4, not_provided=1}.
BS1
Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.000643 (98/152328) while in subpopulation NFE AF= 0.00134 (91/68032). AF 95% confidence interval is 0.00112. There are 0 homozygotes in gnomad4. There are 38 alleles in male gnomad4 subpopulation. Median coverage is 32. 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 rank MANE Protein UniProt
POLR3BNM_018082.6 linkc.1244T>C p.Met415Thr missense_variant Exon 13 of 28 ENST00000228347.9 NP_060552.4 Q9NW08-1Q7Z3R8
POLR3BNM_001160708.2 linkc.1070T>C p.Met357Thr missense_variant Exon 13 of 28 NP_001154180.1 Q9NW08-2
POLR3BXM_017019621.3 linkc.1244T>C p.Met415Thr missense_variant Exon 13 of 26 XP_016875110.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POLR3BENST00000228347.9 linkc.1244T>C p.Met415Thr missense_variant Exon 13 of 28 1 NM_018082.6 ENSP00000228347.4 Q9NW08-1
POLR3BENST00000539066.5 linkc.1070T>C p.Met357Thr missense_variant Exon 13 of 28 2 ENSP00000445721.1 Q9NW08-2
POLR3BENST00000549569.1 linkc.*9T>C downstream_gene_variant 4 ENSP00000448398.1 F8VRU2
POLR3BENST00000549195.1 linkn.*72T>C downstream_gene_variant 3

Frequencies

GnomAD3 genomes
AF:
0.000644
AC:
98
AN:
152210
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000121
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.00134
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000554
AC:
139
AN:
251068
Hom.:
0
AF XY:
0.000553
AC XY:
75
AN XY:
135658
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000924
Gnomad NFE exome
AF:
0.00115
Gnomad OTH exome
AF:
0.000490
GnomAD4 exome
AF:
0.000895
AC:
1308
AN:
1461464
Hom.:
1
Cov.:
32
AF XY:
0.000851
AC XY:
619
AN XY:
727058
show subpopulations
Gnomad4 AFR exome
AF:
0.000120
Gnomad4 AMR exome
AF:
0.0000447
Gnomad4 ASJ exome
AF:
0.0000383
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0000936
Gnomad4 NFE exome
AF:
0.00114
Gnomad4 OTH exome
AF:
0.000497
GnomAD4 genome
AF:
0.000643
AC:
98
AN:
152328
Hom.:
0
Cov.:
32
AF XY:
0.000510
AC XY:
38
AN XY:
74494
show subpopulations
Gnomad4 AFR
AF:
0.000120
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00134
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.00115
Hom.:
0
Bravo
AF:
0.000578
TwinsUK
AF:
0.00135
AC:
5
ALSPAC
AF:
0.000778
AC:
3
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00105
AC:
9
ExAC
AF:
0.000618
AC:
75
EpiCase
AF:
0.00158
EpiControl
AF:
0.000771

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:9Uncertain:9Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:3Uncertain:3
Mar 07, 2025
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 35316923, 27512013, 33726816, 34440436, 32870266, 27029625, 25133958, 32345981, 22855961, 37273706, 36268624) -

Oct 23, 2020
Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

May 30, 2018
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 415 of the POLR3B protein (p.Met415Thr). This variant is present in population databases (rs199504211, gnomAD 0.1%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with clinical features of autosomal recessive POLR3B-related conditions (PMID: 25133958, 27029625, 27512013, 34440436, 36268624, 37273706). ClinVar contains an entry for this variant (Variation ID: 285205). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt POLR3B protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Jul 12, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

BS1, PP3, PM3_strong -

Jan 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

POLR3B: PM3:Very Strong, PM2:Supporting, PP2 -

Hypomyelinating leukodystrophy 8 with or without oligodontia and-or hypogonadotropic hypogonadism Pathogenic:3Uncertain:2Other:1
Jan 01, 2019
Institute of Human Genetics, University of Leipzig Medical Center
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 21, 2021
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 24, 2023
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: curation

The p.Met415Thr variant in POLR3B has been reported in 7 individuals with 4H leukodystrophy (PMID: 27512013, 25133958, 27029625, 33726816, 34440436, 31996231) and has been identified in 0.11% (149/128840) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs199504211). Although this variant has been seen in the general population in a heterozygous state, its frequency is not high enough to rule out a pathogenic role. This variant has also been reported in ClinVar (Variation ID#: 285205) and has been interpreted as VUS by Eurofins NTD (LLC) and Fulgent Genetics, and likely pathogenic or pathogenic by Institute of Human Genetics (University of Leipzig Medical Center), Institute of Medical Genetics and Applied Genomics (University Hospital Tübingen), GeneDx, and GeneReviews. Of the 7 affected individuals, 2 were compound heterozygotes that carried reported pathogenic variants in trans and with unknown phase, which increases the likelihood that the p.Met415Thr variant is pathogenic (VariationID: 620581; PMID: 31996231, 27512013). Computational prediction tools and conservation analyses suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. The number of missense variants reported in POLR3B in the general population is lower than expected, suggesting there is little benign variation in this gene and slightly increasing the possibility that a missense variant in this gene may not be tolerated. In summary, the clinical significance of the p.Met415Thr variant is uncertain. ACMG/AMP Criteria applied: PP3, PM3, PP2 (Richards 2015). -

May 30, 2022
Undiagnosed Diseases Network, NIH
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Oct 31, 2022
Genetics and Molecular Pathology, SA Pathology
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
GeneReviews
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Inborn genetic diseases Pathogenic:1
Aug 04, 2022
Ambry Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.1244T>C (p.M415T) alteration is located in exon 13 (coding exon 13) of the POLR3B gene. This alteration results from a T to C substitution at nucleotide position 1244, causing the methionine (M) at amino acid position 415 to be replaced by a threonine (T)._x000D_ _x000D_ Based on the available evidence, the c.1244T>C p.M415T alteration is classified as likely pathogenic for autosomal recessive POLR3B-related hypomyelinating leukodystrophy; however, it is unlikely to be causative of autosomal dominant POLR3B-related Charcot-Marie-Tooth disease type 1. Based on data from gnomAD, the C allele has an overall frequency of 0.06% (160/282446) total alleles studied. The highest observed frequency was 0.12% (149/128840) of European (non-Finnish) alleles. This variant has been reported to be compound heterozygous with other POLR3B variants in multiple individuals with features consistent with POLR3B-related hypomyelinating leukodystrophy (Fogel, 2014; La Piana, 2016; Richards, 2017; Barbosa-Gouveia, 2021; Gach, 2022). This amino acid position is highly conserved in available vertebrate species. The in silico prediction for this alteration is inconclusive. Based on the available evidence, this alteration is classified as likely pathogenic. -

See cases Pathogenic:1
Nov 16, 2020
Laboratorio de Genetica e Diagnostico Molecular, Hospital Israelita Albert Einstein
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

ACMG classification criteria: PS4, PM3, PP3 -

Hypomyelinating leukodystrophy 8 with or without oligodontia and-or hypogonadotropic hypogonadism;C5676914:Charcot-Marie-Tooth disease, demyelinating, IIA 1I Pathogenic:1
Apr 10, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not specified Uncertain:1
Mar 13, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: POLR3B c.1244T>C (p.Met415Thr) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00055 in 251068 control chromosomes. c.1244T>C has been reported in the literature in individuals affected with POLR3-Related Leukodystrophy, cerebellar ataxia, isolated hypogonadotropic hypogonadism (Barbosa-Gouveia_2021, Fogel_2014, Richards_2017) and in an individual with clinical features of ataxia, myopia, developmental delay, short stature, and cerebellar atrophy (La Piana_2016). In all cases, the second allele reported in the patients were of unknown or uncertain significance. These reports do not provide unequivocal conclusions about association of the variant with POLR3-Related Leukodystrophy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. 11 ClinVar submitters have submitted clinical-significance assessments for this variant to ClinVar after 2014. Multiple laboratories reported the variant with conflicting assessments including uncertain significance (n=5), likely pathogenic (n=4), or pathogenic (n=2). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Amenorrhea Uncertain:1
Mar 08, 2021
Yale Center for Mendelian Genomics, Yale University
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: literature only

- -

POLR-related leukodystrophy Uncertain:1
Sep 14, 2023
Illumina Laboratory Services, Illumina
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The POLR3B c.1244T>C (p.Met415Thr) missense variant has been reported in at least five individuals with variable presentations of POLR3-related conditions, including ataxia, hypogonadotropic hypogonadism, white matter abnormalities on brain MRI, and myopia (PMID: 25133958; 27029625; 27512013; 33726816; 34440436). In two of these cases, the variant co-occurred with a predicted loss of function variant, and in at least three other cases it has been reported in trans with another missense variant. The highest frequency of this allele in the Genome Aggregation Database is 0.001337 in the European (non-Finnish) population (version 3.1.2). Computational evidence suggests the variant may impact the gene or gene product. Based on the available evidence, the c.1244T>C (p.Met415Thr) variant is classified as a variant of uncertain significance for POLR3-related leukodystrophy. -

Hypogonadotropic hypogonadism 7 with or without anosmia;C3280644:Hypomyelinating leukodystrophy 8 with or without oligodontia and-or hypogonadotropic hypogonadism;C4706676:Leukoencephalopathy, ataxia, hypodontia, hypomyelination syndrome Uncertain:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.92
BayesDel_addAF
Benign
-0.092
T
BayesDel_noAF
Uncertain
0.050
CADD
Pathogenic
26
DANN
Uncertain
0.99
DEOGEN2
Benign
0.31
T;.
Eigen
Uncertain
0.51
Eigen_PC
Uncertain
0.59
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Pathogenic
0.32
D
MetaRNN
Uncertain
0.59
D;D
MetaSVM
Uncertain
-0.23
T
MutationAssessor
Uncertain
2.1
M;.
PrimateAI
Pathogenic
0.91
D
PROVEAN
Uncertain
-2.9
D;D
REVEL
Pathogenic
0.82
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.0020
D;D
Polyphen
0.42
B;.
Vest4
0.98
MVP
0.78
MPC
1.1
ClinPred
0.13
T
GERP RS
5.8
Varity_R
0.71
gMVP
0.91

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

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

Other links and lift over

dbSNP: rs199504211; hg19: chr12-106821117; COSMIC: COSV99075432; COSMIC: COSV99075432; API