rs869312389

Positions:

• chrX-101398866-CTT-C
• chrX-101398866-CTT-CT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000169.3(GLA):​c.718_719delAA​(p.Lys240fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000914 in 1,093,569 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 9.1e-7 (0 hom. 0 hem.)
• Consequence: GLA NM_000169.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 2.68

Genes affected

GLA (HGNC:4296): (galactosidase alpha) This gene encodes a homodimeric glycoprotein that hydrolyses the terminal alpha-galactosyl moieties from glycolipids and glycoproteins. This enzyme predominantly hydrolyzes ceramide trihexoside, and it can catalyze the hydrolysis of melibiose into galactose and glucose. A variety of mutations in this gene affect the synthesis, processing, and stability of this enzyme, which causes Fabry disease, a rare lysosomal storage disorder that results from a failure to catabolize alpha-D-galactosyl glycolipid moieties. [provided by RefSeq, Jul 2008]

RPL36A-HNRNPH2 (HGNC:48349): (RPL36A-HNRNPH2 readthrough) This locus represents naturally occurring read-through transcription between the neighboring ribosomal protein L36a and heterogeneous nuclear ribonucleoprotein H2 (H') genes on chromosome X. The read-through transcript produces a protein with similarity to the protein encoded by the upstream locus, ribosomal protein L36a. Alternatively spliced transcript variants have been identified. [provided by RefSeq, Jan 2011]

GLA (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-101398866-CTT-C is Pathogenic according to our data. Variant chrX-101398866-CTT-C is described in ClinVar as [Pathogenic]. Clinvar id is 222371.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-101398866-CTT-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GLA	NM_000169.3	c.718_719delAA	p.Lys240fs	frameshift_variant	5/7	ENST00000218516.4	NP_000160.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GLA	ENST00000218516.4	c.718_719delAA	p.Lys240fs	frameshift_variant	5/7	1	NM_000169.3	ENSP00000218516.4
RPL36A-HNRNPH2	ENST00000409170.3	c.300+3411_300+3412delTT		intron_variant		4		ENSP00000386655.4

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 9.14e-7 AC: 1 AN: 1093569 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 359013

Gnomad4 AFR exome AF: 0.00

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: 0.00000119

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Fabry disease Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Centogene AG - the Rare Disease Company	Mar 15, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Sep 07, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 15, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Dec 05, 2018	Variant summary: GLA c.718_719delAA (p.Lys240GlufsX9) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory (eg. p.Gln250X, p.Arg301X, p.Arg332fsX7). The variant was absent in 178766 control chromosomes. c.718_719delAA has been reported in the literature in multiple individuals affected with Fabry Disease (Blanch_1996, Bono_2011, Germain_2002, Nakano_2013, Shimotori_2007). These data indicate that the variant is very likely to be associated with disease. Enzyme activity assessed in transfected COS-7 cells showed the variant to result in <10% normal enzyme activity, with no response to 1-deoxygalactonojirimycin treatment (Shimotori_2007). One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 04, 2023	This sequence change creates a premature translational stop signal (p.Lys240Glufs*9) in the GLA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GLA are known to be pathogenic (PMID: 10666480, 12175777). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individuals with Fabry disease (PMID: 8069316, 18205205, 22551898, 24582695, 27560961). ClinVar contains an entry for this variant (Variation ID: 222371). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 23, 2018	The c.718_719delAA variant has been reported previously in association with Fabry disease using alternative nomenclature (Davies et al., 1994; Sueoka et al., 2015). The c.718_719delAA variant is not observed in large population cohorts (Lek et al., 2016). The deletion causes a frameshift starting with codon Lysine 240, changes this amino acid to a Glutamic Acid residue and creates a premature Stop codon at position 9 of the new reading frame, denoted p.Lys240GlufsX9. This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. In summary, we interpret c.718_719delAA as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Aug 22, 2017	- -

Computational scores

Source: dbNSFP v4.3

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

Other links and lift over

dbSNP: rs869312389; hg19: chrX-100653854;