16-17141299-G-C

Variant names:

• chr16-17141299-G-C
• rs587777366
• NM_022166.4:c.1441C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_022166.4(XYLT1):​c.1441C>G​(p.Arg481Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R481W) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: XYLT1 NM_022166.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.60
• 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: Labcorp Genetics (formerly Invitae), G2P
• 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_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-17141299-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 127234.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.854

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_022166.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	XYLT1	NM_022166.4	MANE Select	c.1441C>G	p.Arg481Gly	missense	Exon 7 of 12	NP_071449.1	Q86Y38

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	XYLT1	ENST00000261381.7	TSL:1 MANE Select	c.1441C>G	p.Arg481Gly	missense	Exon 7 of 12	ENSP00000261381.6	Q86Y38
	XYLT1	ENST00000933757.1		c.1441C>G	p.Arg481Gly	missense	Exon 7 of 12	ENSP00000603816.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461888 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000348 AC: 3 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Pathogenic	26
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.38	T
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Uncertain	0.93	D
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.85	D
MetaSVM	Benign	-0.82	T
MutationAssessor	Pathogenic	3.8	H
PhyloP100		2.6
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-6.5	D
REVEL	Uncertain	0.55
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.93
MutPred		0.55		Loss of solvent accessibility (P = 0.0159)
MVP		0.18
MPC		0.95
ClinPred		0.99	D
GERP RS		3.9
Varity_R		0.97
gMVP		0.95

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: rs587777366; hg19: chr16-17235156;