rs63751297

Variant names:

• chr17-3483497-A-G
• rs63751297
• NM_000049.4:c.433-2A>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_000049.4(ASPA):​c.433-2A>G variant causes a splice acceptor, intron change. 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 predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: ASPA NM_000049.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4 O:1
• Conservation: PhyloP100: 6.82
• Publications: 2 publications found

Genes affected

ASPA (HGNC:756): (aspartoacylase) This gene encodes an enzyme that catalyzes the conversion of N-acetyl_L-aspartic acid (NAA) to aspartate and acetate. NAA is abundant in the brain where hydrolysis by aspartoacylase is thought to help maintain white matter. This protein is an NAA scavenger in other tissues. Mutations in this gene cause Canavan disease. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2008]

SPATA22 (HGNC:30705): (spermatogenesis associated 22) Predicted to be involved in regulation of meiotic cell cycle. Predicted to act upstream of or within several processes, including fertilization; gamete generation; and meiosis I cell cycle process. Predicted to be located in chromosome. [provided by Alliance of Genome Resources, Apr 2022]

SPATA22 Gene-Disease associations (from GenCC):

• genetic infertility

  Inheritance: AR Classification: MODERATE Submitted by: PanelApp Australia
• infertility disorder

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.09978768 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.1, offset of -24, new splice context is: acatacggtttttacctaAGaaa. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-3483497-A-G is Pathogenic according to our data. Variant chr17-3483497-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 40118.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000049.4. 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
	ASPA	NM_000049.4	MANE Select	c.433-2A>G		splice_acceptor intron	N/A	NP_000040.1	Q6FH48
	SPATA22	NM_001321337.2		c.-73-14099T>C		intron	N/A	NP_001308266.1	A0A140VJV9
	SPATA22	NM_001321336.2		c.-73-14099T>C		intron	N/A	NP_001308265.1	F5GWB9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ASPA	ENST00000263080.3	TSL:1 MANE Select	c.433-2A>G		splice_acceptor intron	N/A	ENSP00000263080.2	P45381
	ASPA	ENST00000456349.6	TSL:1	c.433-2A>G		splice_acceptor intron	N/A	ENSP00000409976.2	P45381
	SPATA22	ENST00000541913.5	TSL:2	c.-73-14099T>C		intron	N/A	ENSP00000441920.1	F5GWB9

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	-	-	Canavan Disease, Familial Form (1)
1	-	-	Inborn genetic diseases (1)
1	-	-	not provided (1)
1	-	-	Spongy degeneration of central nervous system (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.26
CADD	Pathogenic	28
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		6.8
GERP RS		5.4
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.98		Position offset: 2

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

Other links and lift over

dbSNP: rs63751297; hg19: chr17-3386791;