2-233672493-C-T

Position:

• chr2-233672493-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_021027.3(UGT1A9):​c.559C>T​(p.Leu187Phe) variant causes a missense 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. 13/20 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)
• Consequence: UGT1A9 NM_021027.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.163

Genes affected

UGT1A9 (HGNC:12541): (UDP glucuronosyltransferase family 1 member A9) This gene encodes a UDP-glucuronosyltransferase, an enzyme of the glucuronidation pathway that transforms small lipophilic molecules, such as steroids, bilirubin, hormones, and drugs, into water-soluble, excretable metabolites. This gene is part of a complex locus that encodes several UDP-glucuronosyltransferases. The locus includes thirteen unique alternate first exons followed by four common exons. Four of the alternate first exons are considered pseudogenes. Each of the remaining nine 5' exons may be spliced to the four common exons, resulting in nine proteins with different N-termini and identical C-termini. Each first exon encodes the substrate binding site, and is regulated by its own promoter. The enzyme encoded by this gene is active on phenols. [provided by RefSeq, Jul 2008]

UGT1A10 (HGNC:12531): (UDP glucuronosyltransferase family 1 member A10) This gene encodes a UDP-glucuronosyltransferase, an enzyme of the glucuronidation pathway that transforms small lipophilic molecules, such as steroids, bilirubin, hormones, and drugs, into water-soluble, excretable metabolites. This gene is part of a complex locus that encodes several UDP-glucuronosyltransferases. The locus includes thirteen unique alternate first exons followed by four common exons. Four of the alternate first exons are considered pseudogenes. Each of the remaining nine 5' exons may be spliced to the four common exons, resulting in nine proteins with different N-termini and identical C-termini. Each first exon encodes the substrate binding site, and is regulated by its own promoter. The enzyme encoded by this gene has glucuronidase activity on mycophenolic acid, coumarins, and quinolines. [provided by RefSeq, Jul 2008]

UGT1A8 (HGNC:12540): (UDP glucuronosyltransferase family 1 member A8) This gene encodes a UDP-glucuronosyltransferase, an enzyme of the glucuronidation pathway that transforms small lipophilic molecules, such as steroids, bilirubin, hormones, and drugs, into water-soluble, excretable metabolites. This gene is part of a complex locus that encodes several UDP-glucuronosyltransferases. The locus includes thirteen unique alternate first exons followed by four common exons. Four of the alternate first exons are considered pseudogenes. Each of the remaining nine 5' exons may be spliced to the four common exons, resulting in nine proteins with different N-termini and identical C-termini. Each first exon encodes the substrate binding site, and is regulated by its own promoter. The enzyme encoded by this gene has glucuronidase activity with many substrates including coumarins, phenols, anthraquinones, flavones, and some opioids. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.42305323).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
UGT1A9	NM_021027.3	c.559C>T	p.Leu187Phe	missense_variant	1/5	ENST00000354728.5
UGT1A10	NM_019075.4	c.855+35116C>T		intron_variant		ENST00000344644.10
UGT1A8	NM_019076.5	c.855+53931C>T		intron_variant		ENST00000373450.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
UGT1A9	ENST00000354728.5	c.559C>T	p.Leu187Phe	missense_variant	1/5	1	NM_021027.3	P1
UGT1A10	ENST00000344644.10	c.855+35116C>T		intron_variant		1	NM_019075.4	P1
UGT1A8	ENST00000373450.5	c.855+53931C>T		intron_variant		1	NM_019076.5	P1
UGT1A10	ENST00000373445.1	c.855+35116C>T		intron_variant		1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

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

Mar 28, 2024

The c.559C>T (p.L187F) alteration is located in exon 1 (coding exon 1) of the UGT1A9 gene. This alteration results from a C to T substitution at nucleotide position 559, causing the leucine (L) at amino acid position 187 to be replaced by a phenylalanine (F). 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	0.22
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.55
CADD	Benign	12
DANN	Uncertain	1.0
DEOGEN2	Benign	0.24	T
Eigen	Benign	-0.19
Eigen_PC	Benign	-0.41
FATHMM_MKL	Benign	0.087	N
LIST_S2	Benign	0.21	T
M_CAP	Benign	0.012	T
MetaRNN	Benign	0.42	T
MetaSVM	Benign	-0.80	T
MutationAssessor	Uncertain	2.2	M
MutationTaster	Benign	1.0	N;N;N;N
PROVEAN	Benign	-1.5	N
REVEL	Benign	0.13
Sift	Benign	0.11	T
Sift4G	Benign	0.10	T
Polyphen		0.99	D
Vest4		0.082
MutPred		0.52		Loss of helix (P = 0.1706);
MVP		0.61
MPC		0.33
ClinPred		0.65	D
GERP RS		1.5
Varity_R		0.084
gMVP		0.15

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs2074229002; hg19: chr2-234581139;