17-44960201-A-G

Position:

• chr17-44960201-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_006688.5(C1QL1):​c.764T>C​(p.Ile255Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,798 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: C1QL1 NM_006688.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.90

Genes affected

C1QL1 (HGNC:24182): (complement C1q like 1) Predicted to enable signaling receptor binding activity. Predicted to act upstream of or within maintenance of synapse structure; motor learning; and neuron remodeling. Predicted to be located in several cellular components, including climbing fiber; presynapse; and synaptic cleft. Predicted to be part of collagen trimer. [provided by Alliance of Genome Resources, Apr 2022]

NMT1 (HGNC:7857): (N-myristoyltransferase 1) Myristate, a rare 14-carbon saturated fatty acid, is cotranslationally attached by an amide linkage to the N-terminal glycine residue of cellular and viral proteins with diverse functions. N-myristoyltransferase (NMT; EC 2.3.1.97) catalyzes the transfer of myristate from CoA to proteins. N-myristoylation appears to be irreversible and is required for full expression of the biologic activities of several N-myristoylated proteins, including the alpha subunit of the signal-transducing guanine nucleotide-binding protein (G protein) GO (GNAO1; MIM 139311) (Duronio et al., 1992 [PubMed 1570339]).[supplied by OMIM, Nov 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.932

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
C1QL1	NM_006688.5	c.764T>C	p.Ile255Thr	missense_variant	2/2	ENST00000253407.4	NP_006679.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
C1QL1	ENST00000253407.4	c.764T>C	p.Ile255Thr	missense_variant	2/2	1	NM_006688.5	ENSP00000253407.2
NMT1	ENST00000678938.1	c.-110+2139A>G		intron_variant				ENSP00000503621.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461798 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727212

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 23, 2023

The c.764T>C (p.I255T) alteration is located in exon 2 (coding exon 2) of the C1QL1 gene. This alteration results from a T to C substitution at nucleotide position 764, causing the isoleucine (I) at amino acid position 255 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.010
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Benign	-0.28	T
MutationAssessor	Pathogenic	3.2	M
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.7	D
REVEL	Uncertain	0.50
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0040	D
Polyphen		0.93	P
Vest4		0.71
MutPred		0.82		Loss of stability (P = 0.0053);
MVP		0.48
ClinPred		1.0	D
GERP RS		4.4
Varity_R		0.70
gMVP		0.51

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: rs1047987532; hg19: chr17-43037569;