NM_003124.5:c.448_450delAGAinsGGC

Variant names:

• chr2-72888457-AGA-GGC
• NM_003124.5:c.448_450delAGAinsGGC
• SPR p.Arg150Gly

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PS1_Very_Strong PM1 PP2

The NM_003124.5(SPR):​c.448_450delAGAinsGGC​(p.Arg150Gly) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar.

• Frequency: Genomes: not found (cov: 33)
• Consequence: SPR NM_003124.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.95
• Publications: 0 publications found

Genes affected

SPR (HGNC:11257): (sepiapterin reductase) This gene encodes an aldo-keto reductase that catalyzes the NADPH-dependent reduction of pteridine derivatives and is important in the biosynthesis of tetrahydrobiopterin (BH4). Mutations in this gene result in DOPA-responsive dystonia due to sepiaterin reductase deficiency. A pseudogene has been identified on chromosome 1. [provided by RefSeq, Jul 2008]

SPR Gene-Disease associations (from GenCC):

• dopa-responsive dystonia due to sepiapterin reductase deficiency

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, G2P, PanelApp Australia, Genomics England PanelApp, ClinGen, Orphanet
• BH4-deficient hyperphenylalaninemia A

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PS1: Transcript NM_003124.5 (SPR) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a chain Sepiapterin reductase (size 260) in uniprot entity SPRE_HUMAN there are 9 pathogenic changes around while only 2 benign (82%) in NM_003124.5
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 6 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 0.7325 (below the threshold of 3.09). Trascript score misZ: -0.70614 (below the threshold of 3.09). GenCC associations: The gene is linked to dopa-responsive dystonia due to sepiapterin reductase deficiency, BH4-deficient hyperphenylalaninemia A.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003124.5. 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
	SPR	NM_003124.5	MANE Select	c.448_450delAGAinsGGC	p.Arg150Gly	missense	N/A	NP_003115.1	P35270

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPR	ENST00000234454.6	TSL:1 MANE Select	c.448_450delAGAinsGGC	p.Arg150Gly	missense	N/A	ENSP00000234454.5	P35270
	SPR	ENST00000871611.1		c.448_450delAGAinsGGC	p.Arg150Gly	missense	N/A	ENSP00000541670.1
	SPR	ENST00000871609.1		c.424_426delAGAinsGGC	p.Arg142Gly	missense	N/A	ENSP00000541668.1

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		4.0

Splicing

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr2-73115586;