rs767848384

chr2-73599520-A-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_001378454.1(ALMS1):c.11667A>G(p.Ala3889=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,172 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: ALMS1 NM_001378454.1 splice_region, synonymous
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 1.41

Genes affected

ALMS1 (HGNC:428): (ALMS1 centrosome and basal body associated protein) This gene encodes a protein containing a large tandem-repeat domain as well as additional low complexity regions. The encoded protein functions in microtubule organization, particularly in the formation and maintanance of cilia. Mutations in this gene cause Alstrom syndrome. There is a pseudogene for this gene located adjacent in the same region of chromosome 2. Alternative splice variants have been described but their full length nature has not been determined. [provided by RefSeq, Apr 2014]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.39).
• BP7: Synonymous conserved (PhyloP=1.41 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ALMS1	NM_001378454.1	c.11667A>G	p.Ala3889=	splice_region_variant, synonymous_variant	17/23	ENST00000613296.6
ALMS1	NM_015120.4	c.11670A>G	p.Ala3890=	splice_region_variant, synonymous_variant	17/23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ALMS1	ENST00000613296.6	c.11667A>G	p.Ala3889=	splice_region_variant, synonymous_variant	17/23	1	NM_001378454.1	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000402 AC: 1 AN: 248810 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 134984

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000887

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461172 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726900

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000312 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Alstrom syndrome Uncertain:3

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	May 27, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Mar 23, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	May 16, 2022	This sequence change affects codon 3890 of the ALMS1 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the ALMS1 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs767848384, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with ALMS1-related conditions. ClinVar contains an entry for this variant (Variation ID: 235602). Experimental studies and prediction algorithms are not available or were not evaluated, and the effect of this variant on mRNA splicing is currently unknown. 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:1

Uncertain significance, criteria provided, single submitter

clinical testing

Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics

Jan 29, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.39
Cadd	Benign	11
Dann	Benign	0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs767848384; hg19: chr2-73826647;