rs150734270

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 2P and 9B. PM1BP4_StrongBP6BS2

The NM_000512.5(GALNS):​c.1127G>A​(p.Arg376Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00219 in 1,612,536 control chromosomes in the GnomAD database, including 7 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R376W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0017 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0022 ( 7 hom. )

Consequence

GALNS
NM_000512.5 missense

Scores

2
17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:2

Conservation

PhyloP100: -0.122
Variant links:
Genes affected
GALNS (HGNC:4122): (galactosamine (N-acetyl)-6-sulfatase) This gene encodes N-acetylgalactosamine-6-sulfatase which is a lysosomal exohydrolase required for the degradation of the glycosaminoglycans, keratan sulfate, and chondroitin 6-sulfate. Sequence alterations including point, missense and nonsense mutations, as well as those that affect splicing, result in a deficiency of this enzyme. Deficiencies of this enzyme lead to Morquio A syndrome, a lysosomal storage disorder. [provided by RefSeq, Jul 2008]

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 3 uncertain in NM_000512.5
BP4
Computational evidence support a benign effect (MetaRNN=0.008333862).
BP6
Variant 16-88826714-C-T is Benign according to our data. Variant chr16-88826714-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 193597.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=5}.
BS2
High Homozygotes in GnomAdExome4 at 7 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
GALNSNM_000512.5 linkuse as main transcriptc.1127G>A p.Arg376Gln missense_variant 10/14 ENST00000268695.10

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
GALNSENST00000268695.10 linkuse as main transcriptc.1127G>A p.Arg376Gln missense_variant 10/141 NM_000512.5 P1

Frequencies

GnomAD3 genomes
AF:
0.00173
AC:
263
AN:
152210
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000627
Gnomad AMI
AF:
0.00110
Gnomad AMR
AF:
0.00484
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000577
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00222
Gnomad OTH
AF:
0.00382
GnomAD3 exomes
AF:
0.00177
AC:
438
AN:
246992
Hom.:
1
AF XY:
0.00172
AC XY:
231
AN XY:
134474
show subpopulations
Gnomad AFR exome
AF:
0.000254
Gnomad AMR exome
AF:
0.00425
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00120
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000478
Gnomad NFE exome
AF:
0.00219
Gnomad OTH exome
AF:
0.00366
GnomAD4 exome
AF:
0.00224
AC:
3266
AN:
1460208
Hom.:
7
Cov.:
32
AF XY:
0.00213
AC XY:
1546
AN XY:
726372
show subpopulations
Gnomad4 AFR exome
AF:
0.000299
Gnomad4 AMR exome
AF:
0.00479
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000353
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.000115
Gnomad4 NFE exome
AF:
0.00259
Gnomad4 OTH exome
AF:
0.00230
GnomAD4 genome
AF:
0.00173
AC:
263
AN:
152328
Hom.:
0
Cov.:
34
AF XY:
0.00180
AC XY:
134
AN XY:
74486
show subpopulations
Gnomad4 AFR
AF:
0.000625
Gnomad4 AMR
AF:
0.00483
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000578
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00222
Gnomad4 OTH
AF:
0.00378
Alfa
AF:
0.00178
Hom.:
1
Bravo
AF:
0.00233
TwinsUK
AF:
0.00189
AC:
7
ALSPAC
AF:
0.00208
AC:
8
ESP6500AA
AF:
0.000228
AC:
1
ESP6500EA
AF:
0.00186
AC:
16
ExAC
AF:
0.00119
AC:
144
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.00224
EpiControl
AF:
0.00196

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-IV-A Uncertain:2Benign:2
Likely benign, criteria provided, single submitterclinical testingGenome-Nilou LabNov 07, 2021- -
Uncertain significance, criteria provided, single submittercurationLaboratory of Diagnosis and Therapy of Lysosomal Disorders, University of PadovaFeb 01, 2021No evidence available -
Likely benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaApr 27, 2017This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -
Uncertain significance, criteria provided, single submitterclinical testingInvitaeOct 24, 2022This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 376 of the GALNS protein (p.Arg376Gln). This variant is present in population databases (rs150734270, gnomAD 0.4%), including at least one homozygous and/or hemizygous individual. This missense change has been observed in individuals with mucopolysaccharidosis IVA (PMID: 9521421, 15235041). ClinVar contains an entry for this variant (Variation ID: 193597). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt GALNS protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
not provided Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Apr 18, 2016- -
Uncertain significance, criteria provided, single submitterclinical testingGreenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic CenterSep 27, 2021BP4 -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpFeb 23, 2022Variant summary: GALNS c.1127G>A (p.Arg376Gln) results in a conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.0018 in 247092 control chromosomes, predominantly at a frequency of 0.0042 within the Latino subpopulation in the gnomAD database, including 1 homozygote. The observed variant frequency within Latino control individuals in the gnomAD database is approximately 2 fold of the estimated maximal expected allele frequency for a pathogenic variant in GALNS causing Mucopolysaccharidosis Type IVA (Morquio Syndrome A) phenotype (0.002), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Latino origin. c.1127G>A has been reported in the literature in individuals affected with Mucopolysaccharidosis Type IVA (Morquio Syndrome A), including at least one homozygote (Yamada_1998, Tomatsu_2004, Chuang_2021). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance (n=4) and likely benign (n=2). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.061
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Uncertain
-0.080
CADD
Benign
2.3
DANN
Benign
0.90
DEOGEN2
Benign
0.21
T
Eigen
Benign
-1.4
Eigen_PC
Benign
-1.4
FATHMM_MKL
Benign
0.0040
N
LIST_S2
Benign
0.14
T
M_CAP
Benign
0.042
D
MetaRNN
Benign
0.0083
T
MetaSVM
Benign
-0.60
T
MutationAssessor
Benign
-0.53
N
MutationTaster
Benign
1.0
N;N
PrimateAI
Benign
0.20
T
PROVEAN
Benign
0.010
N
REVEL
Uncertain
0.50
Sift
Benign
0.40
T
Sift4G
Benign
0.24
T
Polyphen
0.027
B
Vest4
0.18
MVP
0.75
MPC
0.11
ClinPred
0.0065
T
GERP RS
-2.8
Varity_R
0.036
gMVP
0.57

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs150734270; hg19: chr16-88893122; COSMIC: COSV51938259; API