NM_145649.5:c.1100A>C

Variant names:

• chr6-10626498-A-C
• rs1554139314
• NM_145649.5:c.1100A>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_145649.5(GCNT2):​c.1100A>C​(p.Lys367Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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)
• Consequence: GCNT2 NM_145649.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.68
• Publications: 0 publications found

Genes affected

GCNT2 (HGNC:4204): (glucosaminyl (N-acetyl) transferase 2 (I blood group)) This gene encodes the enzyme responsible for formation of the blood group I antigen. The i and I antigens are distinguished by linear and branched poly-N-acetyllactosaminoglycans, respectively. The encoded protein is the I-branching enzyme, a beta-1,6-N-acetylglucosaminyltransferase responsible for the conversion of fetal i antigen to adult I antigen in erythrocytes during embryonic development. Mutations in this gene have been associated with adult i blood group phenotype. Alternatively spliced transcript variants encoding different isoforms have been described. [provided by RefSeq, Jul 2008]

GCNT2 Gene-Disease associations (from GenCC):

• cataract 13 with adult I phenotype

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• total early-onset cataract

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.906

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_145649.5. 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
	GCNT2	NM_145649.5	MANE Select	c.1100A>C	p.Lys367Thr	missense	Exon 5 of 5	NP_663624.1
	GCNT2	NM_001491.3	MANE Plus Clinical	c.1094A>C	p.Lys365Thr	missense	Exon 3 of 3	NP_001482.1
	GCNT2	NM_001374747.1		c.1100A>C	p.Lys367Thr	missense	Exon 3 of 3	NP_001361676.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GCNT2	ENST00000495262.7	TSL:2 MANE Select	c.1100A>C	p.Lys367Thr	missense	Exon 5 of 5	ENSP00000419411.2
	GCNT2	ENST00000316170.9	TSL:1 MANE Plus Clinical	c.1094A>C	p.Lys365Thr	missense	Exon 3 of 3	ENSP00000314844.3
	GCNT2	ENST00000265012.5	TSL:1	c.1100A>C	p.Lys367Thr	missense	Exon 3 of 3	ENSP00000265012.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Cataract 13 with adult I phenotype (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.37	T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.88	D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.91	D
MetaSVM	Uncertain	-0.15	T
MutationAssessor	Uncertain	2.9	M
PhyloP100		7.7
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Pathogenic	0.68
Sift	Uncertain	0.012	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.89
MutPred		0.76		Loss of methylation at K367 (P = 0.0022)
MVP		0.86
MPC		0.11
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.59
gMVP		0.87
Mutation Taster		=19/81	disease causing

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: rs1554139314; hg19: chr6-10626731;