6-30617930-C-T

Variant names:

• chr6-30617930-C-T
• rs761069966
• NM_014046.4:c.65C>T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_014046.4(MRPS18B):​c.65C>T​(p.Ser22Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000616 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: MRPS18B NM_014046.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.170

Genes affected

MRPS18B (HGNC:14516): (mitochondrial ribosomal protein S18B) 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 28S subunit protein that belongs to the ribosomal protein S18P family. The encoded protein is one of three that has significant sequence similarity to bacterial S18 proteins. The primary sequences of the three human mitochondrial S18 proteins are no more closely related to each other than they are to the prokaryotic S18 proteins. Pseudogenes corresponding to this gene are found on chromosomes 1q and 2q. [provided by RefSeq, Jul 2008]

PPP1R10 (HGNC:9284): (protein phosphatase 1 regulatory subunit 10) This gene encodes a protein phosphatase 1 binding protein. The encoded protein plays a role in many cellular processes including cell cycle progression, DNA repair and apoptosis by regulating the activity of protein phosphatase 1. This gene lies within the major histocompatibility complex class I region on chromosome 6, and alternatively spliced transcript variants have been observed for this gene. [provided by RefSeq, Jul 2012]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.049021125).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MRPS18B	NM_014046.4	c.65C>T	p.Ser22Phe	missense_variant	Exon 1 of 7	ENST00000259873.5	NP_054765.1
MRPS18B	XM_024446408.2	c.65C>T	p.Ser22Phe	missense_variant	Exon 1 of 6		XP_024302176.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MRPS18B	ENST00000259873.5	c.65C>T	p.Ser22Phe	missense_variant	Exon 1 of 7	1	NM_014046.4	ENSP00000259873.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251334 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135854

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461882 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727240

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000629

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Dec 01, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.65C>T (p.S22F) alteration is located in exon 1 (coding exon 1) of the MRPS18B gene. This alteration results from a C to T substitution at nucleotide position 65, causing the serine (S) at amino acid position 22 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	0.10
BayesDel_addAF	Benign	-0.21	T
BayesDel_noAF	Benign	-0.53
CADD	Benign	8.9
DANN	Benign	0.89
DEOGEN2	Benign	0.017	T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.025	N
M_CAP	Benign	0.0067	T
MetaRNN	Benign	0.049	T
MetaSVM	Benign	-0.98	T
MutationAssessor	Benign	0.20	N
PrimateAI	Benign	0.27	T
PROVEAN	Benign	-1.3	N
REVEL	Benign	0.012
Sift	Benign	0.71	T
Sift4G	Benign	0.65	T
Polyphen		0.026	B
Vest4		0.086
MutPred		0.39		Loss of disorder (P = 0.0183);
MVP		0.30
MPC		0.13
ClinPred		0.040	T
GERP RS		1.5
Varity_R		0.040
gMVP		0.40

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

Other links and lift over

dbSNP: rs761069966; hg19: chr6-30585707;