rs201728850

Positions:

• chr2-73601275-A-G

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 2P and 9B. PM2 BP4_Strong BP6 BS1

The NM_001378454.1(ALMS1):​c.11953A>G​(p.Ile3985Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000158 in 1,614,214 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/17 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00014 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00016 (0 hom.)
• Consequence: ALMS1 NM_001378454.1 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6 B:5
• Conservation: PhyloP100: -0.643

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]

ALMS1 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.007161796).
• BP6: Variant 2-73601275-A-G is Benign according to our data. Variant chr2-73601275-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 581362.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=4, Uncertain_significance=5}.
• BS1: Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.000159 (233/1461886) while in subpopulation AMR AF= 0.00134 (60/44724). AF 95% confidence interval is 0.00107. There are 0 homozygotes in gnomad4_exome. There are 124 alleles in male gnomad4_exome subpopulation. Median coverage is 74. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ALMS1	NM_001378454.1	c.11953A>G	p.Ile3985Val	missense_variant	19/23	ENST00000613296.6	NP_001365383.1
ALMS1	NM_015120.4	c.11953A>G	p.Ile3985Val	missense_variant	19/23		NP_055935.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ALMS1	ENST00000613296.6	c.11953A>G	p.Ile3985Val	missense_variant	19/23	1	NM_001378454.1	ENSP00000482968.1

Frequencies

GnomAD3 genomes AF: 0.000145 AC: 22 AN: 152210 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000262

Gnomad ASJ AF: 0.00115

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.000162

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000395 AC: 99 AN: 250352 Hom.: 0 AF XY: 0.000346 AC XY: 47 AN XY: 135758

Gnomad AFR exome AF: 0.0000644

Gnomad AMR exome AF: 0.00168

Gnomad ASJ exome AF: 0.00109

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000163

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000194

Gnomad OTH exome AF: 0.000329

GnomAD4 exome AF: 0.000159 AC: 233 AN: 1461886 Hom.: 0 Cov.: 74 AF XY: 0.000171 AC XY: 124 AN XY: 727246

Gnomad4 AFR exome AF: 0.0000597

Gnomad4 AMR exome AF: 0.00134

Gnomad4 ASJ exome AF: 0.000918

Gnomad4 EAS exome AF: 0.0000504

Gnomad4 SAS exome AF: 0.000197

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000108

Gnomad4 OTH exome AF: 0.000116

GnomAD4 genome AF: 0.000144 AC: 22 AN: 152328 Hom.: 0 Cov.: 33 AF XY: 0.000148 AC XY: 11 AN XY: 74492

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.000261

Gnomad4 ASJ AF: 0.00115

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000162

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000234 Hom.: 0

Bravo AF: 0.000200

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.000330 AC: 40

Asia WGS AF: 0.000577 AC: 2 AN: 3478

EpiCase AF: 0.000491

EpiControl AF: 0.000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6 Benign:5

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Alstrom syndrome Uncertain:3 Benign:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 02, 2022	This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 3986 of the ALMS1 protein (p.Ile3986Val). This variant is present in population databases (rs201728850, gnomAD 0.2%). 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: 581362). 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 valine 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	New York Genome Center	Dec 09, 2021	The heterozygous c.11953A>G (p.Ile3986Val) missense variant identified in the ALMS1 gene has not been reported in affected individuals in the literature. The variant has 0.0003620 allele frequency in the gnomAD (v2.1.1 and v3.1.2) database (102 out of 281762 heterozygous alleles, no homozygotes). This variant is reported as both a Variant of uncertain significance and likely benign associated with Alstrom syndrome in the ClinVar database (Variation ID: 581362). The variant affects a weakly conserved residue (Ile3986) of ALMS1 protein and is predicted neutral by multiple in silico prediction tools (CADD score = 6.015, REVEL score= 0.243). Based on the available evidence, the heterozygous c.11953A>G (p.Ile3986Val) missense variant identified in the ALMS1 gene is reported as a Variant of Uncertain Significance. -
Likely benign, no assertion criteria provided	clinical testing	Natera, Inc.	Apr 23, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Oct 31, 2018	- -
Likely benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	May 18, 2021	- -

not specified Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	May 01, 2019	- -
Likely benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Oct 04, 2019	The p.Ile3986Val variant in ALMS1 is classified as likely benign because it has been identified in 0.1% (59/35436) of Latino chromosomes by gnomAD (http://gnomad.broadinstitute.org), and computational prediction tools predict that this variant does not impact the protein. ACMG/AMP Criteria applied: BS1_Supporting, BP4. -

not provided Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jul 01, 2024	ALMS1: BP4 -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 03, 2024	In silico analysis indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Retinal dystrophy Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg

Jan 01, 2022

- -

Cardiovascular phenotype Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 14, 2019

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	0.065
BayesDel_addAF	Benign	-0.37	T
BayesDel_noAF	Benign	-0.33
CADD	Benign	0.0040
DANN	Benign	0.28
DEOGEN2	Benign	0.012	T;.
Eigen	Benign	-1.5
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.016	N
LIST_S2	Benign	0.56	T;T
M_CAP	Benign	0.0018	T
MetaRNN	Benign	0.0072	T;T
MetaSVM	Benign	-0.91	T
PrimateAI	Benign	0.33	T
Sift4G	Benign	0.53	T;T
Vest4		0.040
MVP		0.085
ClinPred		0.0034	T
GERP RS		-3.7
Varity_R		0.017
gMVP		0.046

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: rs201728850; hg19: chr2-73828402;