rs1213279792

chr2-73489942-A-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001378454.1(ALMS1):c.7983A>T(p.Glu2661Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000752 in 1,461,884 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/16 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. E2661K) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: ALMS1 NM_001378454.1 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:1
• Conservation: PhyloP100: 0.0370

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 -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.041142523).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ALMS1	NM_001378454.1	c.7983A>T	p.Glu2661Asp	missense_variant	10/23	ENST00000613296.6
ALMS1	NM_015120.4	c.7986A>T	p.Glu2662Asp	missense_variant	10/23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ALMS1	ENST00000613296.6	c.7983A>T	p.Glu2661Asp	missense_variant	10/23	1	NM_001378454.1	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000281 AC: 7 AN: 249466 Hom.: 0 AF XY: 0.0000369 AC XY: 5 AN XY: 135344

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000203

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000752 AC: 11 AN: 1461884 Hom.: 0 Cov.: 33 AF XY: 0.0000138 AC XY: 10 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000179

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: 0.0000487 Hom.: 0

Bravo AF: 0.0000113

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Alstrom syndrome Uncertain:4

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	May 19, 2022	This sequence change replaces glutamic acid, which is acidic and polar, with aspartic acid, which is acidic and polar, at codon 2662 of the ALMS1 protein (p.Glu2662Asp). This variant is present in population databases (no rsID available, gnomAD 0.02%). 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: 529394). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Not Available"; Align-GVGD: "Not Available". The aspartic acid amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	May 03, 2022	- -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Oct 04, 2017	- -

Cardiovascular phenotype Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

May 08, 2021

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.075
BayesDel_addAF	Benign	-0.42	T
BayesDel_noAF	Benign	-0.56
Cadd	Benign	12
Dann	Benign	0.73
DEOGEN2	Benign	0.0059	T;.;.
Eigen	Benign	-0.80
Eigen_PC	Benign	-0.59
FATHMM_MKL	Benign	0.38	N
LIST_S2	Benign	0.62	T;T;T
M_CAP	Benign	0.00076	T
MetaRNN	Benign	0.041	T;T;T
MetaSVM	Benign	-0.98	T
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.29	T
Sift4G	Benign	1.0	T;T;T
Vest4		0.022
MVP		0.10
ClinPred		0.028	T
GERP RS		3.3
Varity_R		0.072
gMVP		0.056

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: rs1213279792; hg19: chr2-73717069;