chr1-151763067-C-G

Position:

• chr1-151763067-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_031420.4(MRPL9):​c.233G>C​(p.Arg78Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MRPL9 NM_031420.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.71

Genes affected

MRPL9 (HGNC:14277): (mitochondrial ribosomal protein L9) This is a nuclear gene encoding a protein component of the 39S subunit of the mitochondrial ribosome. Alternative splicing results in multiple transcript variants. A pseudogene of this gene is found on chromosome 8. [provided by RefSeq, Jul 2014]

OAZ3 (HGNC:8097): (ornithine decarboxylase antizyme 3) The protein encoded by this gene belongs to the ornithine decarboxylase antizyme family, which plays a role in cell growth and proliferation by regulating intracellular polyamine levels. Expression of antizymes requires +1 ribosomal frameshifting, which is enhanced by high levels of polyamines. Antizymes in turn bind to and inhibit ornithine decarboxylase (ODC), the key enzyme in polyamine biosynthesis; thus, completing the auto-regulatory circuit. This gene encodes antizyme 3, the third member of the antizyme family. Like antizymes 1 and 2, antizyme 3 inhibits ODC activity and polyamine uptake; however, it does not stimulate ODC degradation. Also, while antizymes 1 and 2 have broad tissue distribution, expression of antizyme 3 is restricted to haploid germ cells in testis, suggesting a distinct role for this antizyme in spermiogenesis. Antizyme 3 gene knockout studies showed that homozygous mutant male mice were infertile, and indicated the likely role of this antizyme in the formation of a rigid connection between the sperm head and tail during spermatogenesis. Alternatively spliced transcript variants encoding different isoforms, including one resulting from the use of non-AUG (CUG) translation initiation codon, have been found for this gene. [provided by RefSeq, Dec 2014]

ACMG classification

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=0.35059094).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MRPL9	NM_031420.4	c.233G>C	p.Arg78Pro	missense_variant	2/7	ENST00000368830.8
OAZ3	NM_001134939.1	c.-69C>G		5_prime_UTR_variant	1/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MRPL9	ENST00000368830.8	c.233G>C	p.Arg78Pro	missense_variant	2/7	1	NM_031420.4	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461816 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727196

Gnomad4 AFR exome AF: 0.00

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000843 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 12, 2021

The c.233G>C (p.R78P) alteration is located in exon 2 (coding exon 2) of the MRPL9 gene. This alteration results from a G to C substitution at nucleotide position 233, causing the arginine (R) at amino acid position 78 to be replaced by a proline (P). 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	Pathogenic	0.90
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.052	T;.
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Benign	0.58	D
LIST_S2	Benign	0.77	T;T
M_CAP	Benign	0.010	T
MetaRNN	Benign	0.35	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.7	L;.
MutationTaster	Benign	0.89	D;D;D;D
PrimateAI	Uncertain	0.72	T
PROVEAN	Uncertain	-2.8	D;D
REVEL	Benign	0.19
Sift	Benign	0.098	T;T
Sift4G	Benign	0.080	T;T
Polyphen		0.99	D;.
Vest4		0.43
MutPred		0.50		Loss of MoRF binding (P = 0.0107);Loss of MoRF binding (P = 0.0107);
MVP		0.38
MPC		0.89
ClinPred		0.96	D
GERP RS		3.9
Varity_R		0.89
gMVP		0.92

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: rs1490830597; hg19: chr1-151735543;