1-193181011-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_003783.3(B3GALT2):c.552A>C(p.Gln184His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,482 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: B3GALT2 NM_003783.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.527

Genes affected

B3GALT2 (HGNC:917): (beta-1,3-galactosyltransferase 2) This gene is a member of the beta-1,3-galactosyltransferase (beta3GalT) gene family. This family encodes type II membrane-bound glycoproteins with diverse enzymatic functions using different donor substrates (UDP-galactose and UDP-N-acetylglucosamine) and different acceptor sugars (N-acetylglucosamine, galactose, N-acetylgalactosamine). The beta3GalT genes are distantly related to the Drosophila Brainiac gene and have the protein coding sequence contained in a single exon. The beta3GalT proteins also contain conserved sequences not found in the beta4GalT or alpha3GalT proteins. The carbohydrate chains synthesized by these enzymes are designated as type 1, whereas beta4GalT enzymes synthesize type 2 carbohydrate chains. The ratio of type 1:type 2 chains changes during embryogenesis. By sequence similarity, the beta3GalT genes fall into at least two groups: beta3GalT4 and 4 other beta3GalT genes (beta3GalT1-3, beta3GalT5). This gene encodes a protein that functions in N-linked glycoprotein glycosylation and shows strict donor substrate specificity for UDP-galactose. [provided by RefSeq, Jul 2008]

CDC73 (HGNC:16783): (cell division cycle 73) This gene encodes a tumor suppressor that is involved in transcriptional and post-transcriptional control pathways. The protein is a component of the the PAF protein complex, which associates with the RNA polymerase II subunit POLR2A and with a histone methyltransferase complex. This protein appears to facilitate the association of 3' mRNA processing factors with actively-transcribed chromatin. Mutations in this gene have been linked to hyperparathyroidism-jaw tumor syndrome, familial isolated hyperparathyroidism, and parathyroid carcinoma. [provided by RefSeq, Jul 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11705172).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
B3GALT2	NM_003783.3	c.552A>C	p.Gln184His	missense_variant	2/2	ENST00000367434.5
CDC73	NM_024529.5	c.973-22784T>G		intron_variant		ENST00000367435.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
B3GALT2	ENST00000367434.5	c.552A>C	p.Gln184His	missense_variant	2/2	1	NM_003783.3	P1
CDC73	ENST00000367435.5	c.973-22784T>G		intron_variant		1	NM_024529.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461482 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727028

Gnomad4 AFR exome AF: 0.0000597

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Jan 23, 2024

The c.552A>C (p.Q184H) alteration is located in exon 2 (coding exon 1) of the B3GALT2 gene. This alteration results from a A to C substitution at nucleotide position 552, causing the glutamine (Q) at amino acid position 184 to be replaced by a histidine (H). 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	Benign	0.091
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.55
Cadd	Benign	15
Dann	Benign	0.95
DEOGEN2	Benign	0.22	T
Eigen	Benign	-0.42
Eigen_PC	Benign	-0.23
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.63	T
M_CAP	Benign	0.0064	T
MetaRNN	Benign	0.12	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.90	L
MutationTaster	Benign	1.0	D;D
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-1.4	N
REVEL	Benign	0.045
Sift	Benign	0.15	T
Sift4G	Benign	0.21	T
Polyphen		0.0	B
Vest4		0.082
MutPred		0.51		Gain of methylation at R187 (P = 0.0885);
MVP		0.41
MPC		0.39
ClinPred		0.31	T
GERP RS		3.1
Varity_R		0.11
gMVP		0.61

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-193150141;