chr1-203226749-G-A

Variant names:

• chr1-203226749-G-A
• rs3766537
• NM_003465.3:c.56-879C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_003465.3(CHIT1):​c.56-879C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000466 in 150,114 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.000047 (0 hom., cov: 30)
• Consequence: CHIT1 NM_003465.3 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.604
• Publications: 3 publications found

Genes affected

CHIT1 (HGNC:1936): (chitinase 1) Chitotriosidase is secreted by activated human macrophages and is markedly elevated in plasma of Gaucher disease patients. The expression of chitotriosidase occurs only at a late stage of differentiation of monocytes to activated macrophages in culture. Human macrophages can synthesize a functional chitotriosidase, a highly conserved enzyme with a strongly regulated expression. This enzyme may play a role in the degradation of chitin-containing pathogens. Several alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Jan 2012]

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.95).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003465.3. 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
	CHIT1	NM_003465.3	MANE Select	c.56-879C>T		intron	N/A	NP_003456.1
	CHIT1	NM_001256125.2		c.56-879C>T		intron	N/A	NP_001243054.2
	CHIT1	NR_045784.2		n.93-879C>T		intron	N/A

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHIT1	ENST00000367229.6	TSL:1 MANE Select	c.56-879C>T		intron	N/A	ENSP00000356198.1
	CHIT1	ENST00000491855.5	TSL:1	n.56-879C>T		intron	N/A	ENSP00000423778.1
	CHIT1	ENST00000503786.1	TSL:1	n.56-879C>T		intron	N/A	ENSP00000421617.1

Frequencies

GnomAD3 genomes AF: 0.0000467 AC: 7 AN: 149996 Hom.: 0 Cov.: 30

Gnomad AFR AF: 0.000123

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: 0.0000297

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.0000466 AC: 7 AN: 150114 Hom.: 0 Cov.: 30 AF XY: 0.0000409 AC XY: 3 AN XY: 73412

African (AFR) AF: 0.000123 AC: 5 AN: 40778

American (AMR) AF: 0.00 AC: 0 AN: 15150

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3442

East Asian (EAS) AF: 0.00 AC: 0 AN: 5042

South Asian (SAS) AF: 0.00 AC: 0 AN: 4700

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10502

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 290

European-Non Finnish (NFE) AF: 0.0000298 AC: 2 AN: 67226

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.00 Hom.: 9189

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.95
CADD	Benign	0.31
DANN	Benign	0.58
PhyloP100		-0.60

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: rs3766537; hg19: chr1-203195877;