21-25588870-T-A

Variant names:

• chr21-25588870-T-A
• rs374575344
• NM_017446.4:c.934A>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_017446.4(MRPL39):​c.934A>T​(p.Ile312Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,226 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I312V) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: MRPL39 NM_017446.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.172
• Publications: 0 publications found

Genes affected

MRPL39 (HGNC:14027): (mitochondrial ribosomal protein L39) 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. Two transcript variants encoding distinct isoforms have been described. A pseudogene corresponding to this gene is found on chromosome 5q. [provided by RefSeq, Jul 2008]

MRPL39 Gene-Disease associations (from GenCC):

• mitochondrial disease

  Inheritance: AR Classification: MODERATE Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 1 curated pathogenic missense variants (we use a threshold of 10). The gene has 0 curated benign missense variants. Gene score misZ: -0.37309 (below the threshold of 3.09). Trascript score misZ: -0.3663 (below the threshold of 3.09). GenCC associations: The gene is linked to mitochondrial disease.
• BP4: Computational evidence support a benign effect (MetaRNN=0.10140291).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_017446.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MRPL39	NM_017446.4	MANE Select	c.934A>T	p.Ile312Leu	missense	Exon 9 of 10	NP_059142.3
	MRPL39	NM_080794.4		c.934A>T	p.Ile312Leu	missense	Exon 9 of 11	NP_542984.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MRPL39	ENST00000352957.9	TSL:1 MANE Select	c.934A>T	p.Ile312Leu	missense	Exon 9 of 10	ENSP00000284967.7	Q9NYK5-1
	MRPL39	ENST00000307301.11	TSL:5	c.934A>T	p.Ile312Leu	missense	Exon 9 of 11	ENSP00000305682.7	Q9NYK5-2
	MRPL39	ENST00000925346.1		c.952A>T	p.Ile318Leu	missense	Exon 9 of 10	ENSP00000595405.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152226 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

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

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250786 AF XY: 0.00000738

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 30

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152226 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74376

African (AFR) AF: 0.00 AC: 0 AN: 41448

American (AMR) AF: 0.00 AC: 0 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.000192 AC: 1 AN: 5208

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68042

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Benign	-0.33	T
BayesDel_noAF	Benign	-0.54
CADD	Benign	17
DANN	Benign	0.91
DEOGEN2	Benign	0.015	T
Eigen	Benign	-0.89
Eigen_PC	Benign	-0.86
FATHMM_MKL	Benign	0.20	N
LIST_S2	Benign	0.71	T
M_CAP	Benign	0.0041	T
MetaRNN	Benign	0.10	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.9	L
PhyloP100		0.17
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-0.98	N
REVEL	Benign	0.14
Sift	Benign	0.26	T
Sift4G	Benign	0.11	T
Polyphen		0.0	B
Vest4		0.28
MutPred		0.34		Loss of methylation at K315 (P = 0.0596)
MVP		0.22
MPC		0.035
ClinPred		0.11	T
GERP RS		-0.36
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.26
gMVP		0.35
Mutation Taster		=91/9	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs374575344; hg19: chr21-26961182;