NM_152419.3:c.12G>C

Variant names:

• chr8-43140508-G-C
• rs1018475767
• NM_152419.3:c.12G>C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_152419.3(HGSNAT):​c.12G>C​(p.Ala4Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. A4A) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: HGSNAT NM_152419.3 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.412
• Publications: 0 publications found

Genes affected

HGSNAT (HGNC:26527): (heparan-alpha-glucosaminide N-acetyltransferase) This gene encodes a lysosomal acetyltransferase, which is one of several enzymes involved in the lysosomal degradation of heparin sulfate. Mutations in this gene are associated with Sanfilippo syndrome C, one type of the lysosomal storage disease mucopolysaccaridosis III, which results from impaired degradation of heparan sulfate. [provided by RefSeq, Jan 2009]

HGSNAT Gene-Disease associations (from GenCC):

• inherited retinal dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• mucopolysaccharidosis type 3

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
• mucopolysaccharidosis type 3C

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, ClinGen, Orphanet, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
• retinitis pigmentosa 73

  Inheritance: AR Classification: STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.79).
• BP6: Variant 8-43140508-G-C is Benign according to our data. Variant chr8-43140508-G-C is described in ClinVar as Likely_benign. ClinVar VariationId is 1541060.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-0.412 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_152419.3. 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
	HGSNAT	NM_152419.3	MANE Select	c.12G>C	p.Ala4Ala	synonymous	Exon 1 of 18	NP_689632.2
	HGSNAT	NM_001363227.2		c.12G>C	p.Ala4Ala	synonymous	Exon 1 of 19	NP_001350156.1
	HGSNAT	NM_001363228.2		c.12G>C	p.Ala4Ala	synonymous	Exon 1 of 16	NP_001350157.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HGSNAT	ENST00000379644.9	TSL:2 MANE Select	c.12G>C	p.Ala4Ala	synonymous	Exon 1 of 18	ENSP00000368965.4	Q68CP4-2
	HGSNAT	ENST00000520704.1	TSL:1	n.-139G>C		non_coding_transcript_exon	Exon 1 of 10	ENSP00000429109.1	E5RJC4
	HGSNAT	ENST00000520704.1	TSL:1	n.-139G>C		5_prime_UTR	Exon 1 of 10	ENSP00000429109.1	E5RJC4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	Mucopolysaccharidosis, MPS-III-C;C4225287:Retinitis pigmentosa 73 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.79
CADD	Benign	5.7
DANN	Benign	0.39
PhyloP100		-0.41
PromoterAI		-0.020	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0

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

Other links and lift over

dbSNP: rs1018475767; hg19: chr8-42995651;