rs121909599

Positions:

• chr4-47949894-C-A
• chr4-47949894-C-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_001379270.1(CNGA1):​c.226G>T​(p.Glu76Ter) variant causes a stop gained, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,590 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CNGA1 NM_001379270.1 stop_gained, splice_region
• Scores: Splicing: ADA: 0.00004517
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 0.109

Genes affected

CNGA1 (HGNC:2148): (cyclic nucleotide gated channel subunit alpha 1) The protein encoded by this gene is involved in phototransduction. Along with another protein, the encoded protein forms a cGMP-gated cation channel in the plasma membrane, allowing depolarization of rod photoreceptors. This represents the last step in the phototransduction pathway. Defects in this gene are a cause of retinitis pigmentosa autosomal recessive (ARRP) disease. Multiple transcript variants have been found for this gene. [provided by RefSeq, Oct 2019]

LOC101927157 (HGNC:):

NIPAL1 (HGNC:27194): (NIPA like domain containing 1) Predicted to enable magnesium ion transmembrane transporter activity. Predicted to be involved in magnesium ion transport. Predicted to be integral component of membrane. Predicted to be active in membrane. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 4-47949894-C-A is Pathogenic according to our data. Variant chr4-47949894-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 16930.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CNGA1	NM_001379270.1	c.226G>T	p.Glu76Ter	stop_gained, splice_region_variant	6/11	ENST00000514170.7	NP_001366199.1
LOC101927157	NR_125879.1	n.479-9130C>A		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CNGA1	ENST00000514170.7	c.226G>T	p.Glu76Ter	stop_gained, splice_region_variant	6/11	5	NM_001379270.1	ENSP00000426862	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461590 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 727102

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Retinitis pigmentosa 49 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Oct 24, 1995

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.070
CADD	Pathogenic	36
DANN	Uncertain	0.98
Eigen	Benign	-0.0027
Eigen_PC	Benign	-0.30
FATHMM_MKL	Benign	0.065	N
MutationTaster	Benign	1.0	A;A;A;A;A
Vest4		0.93
GERP RS		-0.72

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000045
dbscSNV1_RF	Benign	0.0
SpliceAI score (max)		0.36		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.36		Position offset: -3

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

Publications

LitVar

Other links and lift over

dbSNP: rs121909599; hg19: chr4-47951911;