1-225921254-G-T

Variant names:

• chr1-225921254-G-T
• rs876657403
• NM_013328.4:c.751C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 PM5 PP2 PP3_Moderate

The NM_013328.4(PYCR2):​c.751C>A​(p.Arg251Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. R251H) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: PYCR2 NM_013328.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.95
• Publications: 4 publications found

Genes affected

PYCR2 (HGNC:30262): (pyrroline-5-carboxylate reductase 2) This gene belongs to the pyrroline-5-carboxylate reductase family. The encoded mitochondrial protein catalyzes the conversion of pyrroline-5-carboxylate to proline, which is the last step in proline biosynthesis. Alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Nov 2012]

PYCR2 Gene-Disease associations (from GenCC):

• hypomyelinating leukodystrophy 10

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Illumina, Labcorp Genetics (formerly Invitae)
• autosomal recessive primary microcephaly

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000255835 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-225921253-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 992853.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 10 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 0.94826 (below the threshold of 3.09). Trascript score misZ: 0.76229 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive primary microcephaly, hypomyelinating leukodystrophy 10.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.936

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_013328.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PYCR2	NM_013328.4	MANE Select	c.751C>A	p.Arg251Ser	missense	Exon 6 of 7	NP_037460.2
	PYCR2	NM_001271681.2		c.529C>A	p.Arg177Ser	missense	Exon 5 of 6	NP_001258610.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PYCR2	ENST00000343818.11	TSL:1 MANE Select	c.751C>A	p.Arg251Ser	missense	Exon 6 of 7	ENSP00000342502.6
	ENSG00000255835	ENST00000432920.2	TSL:2	c.529C>A	p.Arg177Ser	missense	Exon 5 of 8	ENSP00000414068.2
	PYCR2	ENST00000612039.4	TSL:3	c.529C>A	p.Arg177Ser	missense	Exon 5 of 6	ENSP00000478165.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.21
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Benign	0.12	T
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.36	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Uncertain	0.54	D
MutationAssessor	Uncertain	2.5	M
PhyloP100		8.0
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-4.7	D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.80
MutPred		0.81		Loss of helix (P = 0.1299)
MVP		0.93
MPC		1.3
ClinPred		1.0	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.87
Mutation Taster		=29/71	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: rs876657403; hg19: chr1-226108954;