chr1-1402137-C-G

Position:

chr1-1402137-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_017971.4(MRPL20):c.396G>C(p.Leu132Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,614,164 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000033 ( 1 hom., cov: 33)

Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

MRPL20
NM_017971.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.446

Variant links:

Genes affected

MRPL20 (HGNC:14478): (mitochondrial ribosomal protein L20) Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA. Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology. This gene encodes a 39S subunit protein. A pseudogene corresponding to this gene is found on chromosome 21q. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]

MRPL20 links:

MRPL20 (HGNC:):

MRPL20 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.32388014).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MRPL20	NM_017971.4 linkuse as main transcript	c.396G>C	p.Leu132Phe	missense_variant	4/4	ENST00000344843.12	NP_060441.2	Q9BYC9-1
MRPL20	NM_001318485.2 linkuse as main transcript	c.*432G>C		3_prime_UTR_variant	4/4		NP_001305414.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
MRPL20	ENST00000344843.12 linkuse as main transcript	c.396G>C	p.Leu132Phe	missense_variant	4/4	1	NM_017971.4	ENSP00000341082.7	Q9BYC9-1
MRPL20	ENST00000487659.1 linkuse as main transcript	n.1469G>C		non_coding_transcript_exon_variant	3/3	2
MRPL20	ENST00000493287.5 linkuse as main transcript	n.280G>C		non_coding_transcript_exon_variant	3/3	2
MRPL20	ENST00000492508.1 linkuse as main transcript	c.*432G>C		downstream_gene_variant		2		ENSP00000459994.1	I3L2X1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152206

Hom.:

Cov.:

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:

0.0000147

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251466

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135904

show subpopulations

Gnomad AFR exome

AF:

0.000123

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000144

AC:

AN:

1461840

Hom.:

Cov.:

AF XY:

0.0000138

AC XY:

AN XY:

727218

show subpopulations

Gnomad4 AFR exome

AF:

0.000239

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:

0.00000540

Gnomad4 OTH exome

AF:

0.0000828

GnomAD4 genome

AF:

0.0000328

AC:

AN:

152324

Hom.:

Cov.:

AF XY:

0.0000537

AC XY:

AN XY:

74486

show subpopulations

Gnomad4 AFR

AF:

0.0000722

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.000473

Bravo

AF:

0.0000340

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 01, 2021

The c.396G>C (p.L132F) alteration is located in exon 4 (coding exon 4) of the MRPL20 gene. This alteration results from a G to C substitution at nucleotide position 396, causing the leucine (L) at amino acid position 132 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.19

BayesDel_addAF

Benign

-0.18

BayesDel_noAF

Benign

-0.25

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.077

Eigen

Benign

0.045

Eigen_PC

Benign

-0.030

FATHMM_MKL

Uncertain

0.90

LIST_S2

Benign

0.75

M_CAP

Benign

0.0076

MetaRNN

Benign

0.32

MetaSVM

Benign

-0.89

MutationAssessor

Uncertain

2.1

PrimateAI

Uncertain

0.50

PROVEAN

Benign

-2.0

REVEL

Benign

0.17

Sift

Benign

0.19

Sift4G

Uncertain

0.018

Polyphen

1.0

Vest4

0.57

MutPred

0.29

Loss of helix (P = 0.0196);

MVP

0.42

MPC

0.084

ClinPred

0.35

GERP RS

2.0

Varity_R

0.16

gMVP

0.41

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over