rs777797545

Positions:

• chr4-17487231-A-C
• chr4-17487231-A-G
• chr4-17487231-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP3_Moderate

The NM_000320.3(QDPR):​c.635T>G​(p.Phe212Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,202 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. F212S) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.000013 (0 hom., cov: 32)
• Consequence: QDPR NM_000320.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.03

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a chain Dihydropteridine reductase (size 242) in uniprot entity DHPR_HUMAN there are 36 pathogenic changes around while only 4 benign (90%) in NM_000320.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr4-17487231-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2775915.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.902

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
QDPR	NM_000320.3	c.635T>G	p.Phe212Cys	missense_variant	7/7	ENST00000281243.10
QDPR	NM_001306140.2	c.542T>G	p.Phe181Cys	missense_variant	6/6
QDPR	NR_156494.2	n.562T>G		non_coding_transcript_exon_variant	6/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
QDPR	ENST00000281243.10	c.635T>G	p.Phe212Cys	missense_variant	7/7	1	NM_000320.3	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152202 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152202 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74350

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.65
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.70	D;.
Eigen	Uncertain	0.37
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.81	T;T
M_CAP	Pathogenic	0.48	D
MetaRNN	Pathogenic	0.90	D;D
MetaSVM	Uncertain	0.33	D
MutationAssessor	Pathogenic	3.5	M;.
MutationTaster	Benign	1.0	D;D;D;N
PrimateAI	Uncertain	0.69	T
PROVEAN	Pathogenic	-6.3	D;D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0020	D;D
Polyphen		1.0	D;.
Vest4		0.88
MutPred		0.63		Loss of stability (P = 0.1379);.;
MVP		0.93
MPC		0.89
ClinPred		1.0	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.88
gMVP		0.85

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: rs777797545; hg19: chr4-17488854;