4-17509363-A-C

Variant names:

• chr4-17509363-A-C
• rs104893865
• NM_000320.3:c.106T>G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM2 PM5 PP2 PP3_Moderate PP5_Moderate

The NM_000320.3(QDPR):​c.106T>G​(p.Trp36Gly) variant causes a missense, splice region 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. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W36R) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: QDPR NM_000320.3 missense, splice_region
• Scores: Splicing: ADA: 0.7267
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.89
• Publications: 0 publications found

Genes affected

QDPR (HGNC:9752): (quinoid dihydropteridine reductase) This gene encodes the enzyme dihydropteridine reductase, which catalyzes the NADH-mediated reduction of quinonoid dihydrobiopterin. This enzyme is an essential component of the pterin-dependent aromatic amino acid hydroxylating systems. Mutations in this gene resulting in QDPR deficiency include aberrant splicing, amino acid substitutions, insertions, or premature terminations. Dihydropteridine reductase deficiency presents as atypical phenylketonuria due to insufficient production of biopterin, a cofactor for phenylalanine hydroxylase. [provided by RefSeq, Jul 2008]

QDPR Gene-Disease associations (from GenCC):

• dihydropteridine reductase deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, G2P, Orphanet, Labcorp Genetics (formerly Invitae)

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 chr4-17509363-A-G is described in ClinVar as Pathogenic. ClinVar VariationId is 492.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 24 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Gene score misZ: 0.28456 (below the threshold of 3.09). Trascript score misZ: 0.32173 (below the threshold of 3.09). GenCC associations: The gene is linked to dihydropteridine reductase deficiency.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.843
• PP5: Variant 4-17509363-A-C is Pathogenic according to our data. Variant chr4-17509363-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2504648.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000320.3. 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
	QDPR	NM_000320.3	MANE Select	c.106T>G	p.Trp36Gly	missense splice_region	Exon 2 of 7	NP_000311.2
	QDPR	NR_156494.2		n.142T>G		splice_region non_coding_transcript_exon	Exon 2 of 6
	QDPR	NM_001306140.2		c.105+2587T>G		intron	N/A	NP_001293069.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	QDPR	ENST00000281243.10	TSL:1 MANE Select	c.106T>G	p.Trp36Gly	missense splice_region	Exon 2 of 7	ENSP00000281243.5
	QDPR	ENST00000508623.5	TSL:3	c.106T>G	p.Trp36Gly	missense splice_region	Exon 2 of 5	ENSP00000426377.1
	QDPR	ENST00000513615.5	TSL:2	c.106T>G	p.Trp36Gly	missense splice_region	Exon 2 of 7	ENSP00000422759.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Likely pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Dihydropteridine reductase deficiency (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.69
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.46
CADD	Pathogenic	30
DANN	Uncertain	0.98
DEOGEN2	Benign	0.15	T
Eigen	Uncertain	0.46
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.85	D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.84	D
MetaSVM	Uncertain	0.75	D
MutationAssessor	Pathogenic	3.0	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-12	D
REVEL	Pathogenic	0.78
Sift	Benign	0.29	T
Sift4G	Uncertain	0.034	D
Polyphen		0.52	P
Vest4		0.81
MutPred		0.64		Loss of stability (P = 0.0375)
MVP		0.97
MPC		1.0
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.92
gMVP		0.60
Mutation Taster		=23/77	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.73
dbscSNV1_RF	Benign	0.64
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: rs104893865; hg19: chr4-17510986;