chr16-17198229-C-A

Variant names:

• chr16-17198229-C-A
• rs144531370
• NM_022166.4:c.1272G>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_022166.4(XYLT1):​c.1272G>T​(p.Ala424Ala) variant causes a synonymous 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. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. A424A) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: XYLT1 NM_022166.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -2.98
• Publications: 0 publications found

Genes affected

XYLT1 (HGNC:15516): (xylosyltransferase 1) This locus encodes a xylosyltransferase enzyme. The encoded protein catalyzes transfer of UDP-xylose to serine residues of an acceptor protein substrate. This transfer reaction is necessary for biosynthesis of glycosaminoglycan chains. Mutations in this gene have been associated with increased severity of pseudoxanthoma elasticum.[provided by RefSeq, Nov 2009]

XYLT1 Gene-Disease associations (from GenCC):

• Desbuquois dysplasia 2

  Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Desbuquois dysplasia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• XYLT1-congenital disorder of glycosylation

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.59).
• BP6: Variant 16-17198229-C-A is Benign according to our data. Variant chr16-17198229-C-A is described in ClinVar as Likely_benign. ClinVar VariationId is 1899592.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-2.98 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
XYLT1	NM_022166.4	c.1272G>T	p.Ala424Ala	synonymous_variant	Exon 5 of 12	ENST00000261381.7	NP_071449.1
XYLT1	XM_047434458.1	c.1233G>T	p.Ala411Ala	synonymous_variant	Exon 4 of 11		XP_047290414.1
XYLT1	XM_017023539.3	c.1272G>T	p.Ala424Ala	synonymous_variant	Exon 5 of 12		XP_016879028.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
XYLT1	ENST00000261381.7	c.1272G>T	p.Ala424Ala	synonymous_variant	Exon 5 of 12	1	NM_022166.4	ENSP00000261381.6
XYLT1	ENST00000575674.1	n.400G>T		non_coding_transcript_exon_variant	Exon 3 of 3	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Desbuquois dysplasia 1 Benign:1

Apr 29, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.59
CADD	Benign	0.069
DANN	Benign	0.67
PhyloP100		-3.0

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: rs144531370; hg19: chr16-17292086;