1-23845445-A-G

Variant names:

• chr1-23845445-A-G
• rs143441916
• NM_000147.5:c.*270T>C

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BP4_Strong BS1_Supporting BS2

The NM_000147.5(FUCA1):​c.*270T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000775 in 496,942 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00037 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00095 (2 hom.)
• Consequence: FUCA1 NM_000147.5 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.182
• Publications: 0 publications found

Genes affected

FUCA1 (HGNC:4006): (alpha-L-fucosidase 1) The protein encoded by this gene is a lysosomal enzyme involved in the degradation of fucose-containing glycoproteins and glycolipids. Mutations in this gene are associated with fucosidosis (FUCA1D), which is an autosomal recessive lysosomal storage disease. A pseudogene of this locus is present on chr 2.[provided by RefSeq, Oct 2009]

FUCA1 Gene-Disease associations (from GenCC):

• fucosidosis

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P, Genomics England PanelApp, Ambry Genetics, ClinGen

ACMG classification

Our verdict: Benign. The variant received -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).
• BS1: Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000374 (57/152310) while in subpopulation SAS AF = 0.00456 (22/4826). AF 95% confidence interval is 0.00309. There are 0 homozygotes in GnomAd4. There are 36 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FUCA1	NM_000147.5	c.*270T>C		3_prime_UTR_variant	Exon 8 of 8	ENST00000374479.4	NP_000138.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FUCA1	ENST00000374479.4	c.*270T>C		3_prime_UTR_variant	Exon 8 of 8	1	NM_000147.5	ENSP00000363603.3

Frequencies

GnomAD3 genomes AF: 0.000368 AC: 56 AN: 152192 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00135

Gnomad SAS AF: 0.00435

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.000353

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000952 AC: 328 AN: 344632 Hom.: 2 Cov.: 3 AF XY: 0.00119 AC XY: 220 AN XY: 184566

African (AFR) AF: 0.0000987 AC: 1 AN: 10128

American (AMR) AF: 0.000264 AC: 4 AN: 15166

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 10180

East Asian (EAS) AF: 0.00401 AC: 84 AN: 20938

South Asian (SAS) AF: 0.00407 AC: 176 AN: 43248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 18256

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1416

European-Non Finnish (NFE) AF: 0.000262 AC: 54 AN: 206004

Other (OTH) AF: 0.000466 AC: 9 AN: 19296

GnomAD4 genome AF: 0.000374 AC: 57 AN: 152310 Hom.: 0 Cov.: 32 AF XY: 0.000483 AC XY: 36 AN XY: 74474

African (AFR) AF: 0.0000481 AC: 2 AN: 41572

American (AMR) AF: 0.0000654 AC: 1 AN: 15290

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00135 AC: 7 AN: 5190

South Asian (SAS) AF: 0.00456 AC: 22 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00340 AC: 1 AN: 294

European-Non Finnish (NFE) AF: 0.000353 AC: 24 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2116

Alfa AF: 0.000313 Hom.: 0

Bravo AF: 0.000234

Asia WGS AF: 0.00173 AC: 6 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Fucosidosis Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	1.4
DANN	Benign	0.54
PhyloP100		0.18
Mutation Taster		=100/0	polymorphism

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: rs143441916; hg19: chr1-24171935;