21-25592837-C-T

Variant names:

• chr21-25592837-C-T
• rs1227035820
• NM_017446.4:c.896G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM2 PM5 PP2 PP3_Strong

The NM_017446.4(MRPL39):​c.896G>A​(p.Gly299Asp) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,459,614 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. G299V) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: MRPL39 NM_017446.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.14
• 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: Likely_pathogenic. The variant received 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr21-25592837-C-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1525985.Status of the report is criteria_provided_single_submitter, 1 stars.
• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.97

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.896G>A	p.Gly299Asp	missense	Exon 8 of 10	NP_059142.3
	MRPL39	NM_080794.4		c.896G>A	p.Gly299Asp	missense	Exon 8 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.896G>A	p.Gly299Asp	missense	Exon 8 of 10	ENSP00000284967.7	Q9NYK5-1
	MRPL39	ENST00000307301.11	TSL:5	c.896G>A	p.Gly299Asp	missense	Exon 8 of 11	ENSP00000305682.7	Q9NYK5-2
	MRPL39	ENST00000925346.1		c.914G>A	p.Gly305Asp	missense	Exon 8 of 10	ENSP00000595405.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459614 Hom.: 0 Cov.: 41 AF XY: 0.00 AC XY: 0 AN XY: 726232

African (AFR) AF: 0.00 AC: 0 AN: 33438

American (AMR) AF: 0.00 AC: 0 AN: 44680

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26110

East Asian (EAS) AF: 0.00 AC: 0 AN: 39664

South Asian (SAS) AF: 0.00 AC: 0 AN: 86180

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 9.01e-7 AC: 1 AN: 1110038

Other (OTH) AF: 0.00 AC: 0 AN: 60334

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.56	D
Eigen	Pathogenic	0.74
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.19	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Uncertain	0.40	D
MutationAssessor	Pathogenic	3.0	M
PhyloP100		5.1
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-6.4	D
REVEL	Pathogenic	0.81
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.95
MutPred		0.89		Loss of MoRF binding (P = 0.0774)
MVP		0.93
MPC		0.28
ClinPred		1.0	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.94
gMVP		0.92
Mutation Taster		=7/93	disease causing

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

Other links and lift over

dbSNP: rs1227035820; hg19: chr21-26965149;