NM_001378454.1:c.2065A>G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBS1_Supporting

The NM_001378454.1(ALMS1):​c.2065A>G​(p.Thr689Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000455 in 1,613,726 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/18 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. T689P) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00037 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00046 ( 0 hom. )

Consequence

ALMS1
NM_001378454.1 missense

Scores

1
14

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: -0.492

Publications

3 publications found
Variant links:
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 Gene-Disease associations (from GenCC):
  • Alstrom syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Orphanet, Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.05889699).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000369 (56/151914) while in subpopulation NFE AF = 0.000662 (45/67982). AF 95% confidence interval is 0.000508. There are 0 homozygotes in GnomAd4. There are 25 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

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALMS1NM_001378454.1 linkc.2065A>G p.Thr689Ala missense_variant Exon 8 of 23 ENST00000613296.6 NP_001365383.1
ALMS1NM_015120.4 linkc.2065A>G p.Thr689Ala missense_variant Exon 8 of 23 NP_055935.4 Q8TCU4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALMS1ENST00000613296.6 linkc.2065A>G p.Thr689Ala missense_variant Exon 8 of 23 1 NM_001378454.1 ENSP00000482968.1 Q8TCU4-1

Frequencies

GnomAD3 genomes
AF:
0.000369
AC:
56
AN:
151914
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000121
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000328
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000662
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000261
AC:
65
AN:
248908
AF XY:
0.000281
show subpopulations
Gnomad AFR exome
AF:
0.000194
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000928
Gnomad NFE exome
AF:
0.000497
Gnomad OTH exome
AF:
0.000496
GnomAD4 exome
AF:
0.000464
AC:
679
AN:
1461812
Hom.:
0
Cov.:
82
AF XY:
0.000448
AC XY:
326
AN XY:
727212
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33472
American (AMR)
AF:
0.0000447
AC:
2
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.0000936
AC:
5
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000582
AC:
647
AN:
1111962
Other (OTH)
AF:
0.000397
AC:
24
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
44
88
131
175
219
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
24
48
72
96
120
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000369
AC:
56
AN:
151914
Hom.:
0
Cov.:
32
AF XY:
0.000337
AC XY:
25
AN XY:
74206
show subpopulations
African (AFR)
AF:
0.000121
AC:
5
AN:
41310
American (AMR)
AF:
0.000328
AC:
5
AN:
15242
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000662
AC:
45
AN:
67982
Other (OTH)
AF:
0.000478
AC:
1
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.507
Heterozygous variant carriers
0
3
7
10
14
17
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000444
Hom.:
1
Bravo
AF:
0.000348
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000606
AC:
5
ExAC
AF:
0.000215
AC:
26
EpiCase
AF:
0.000382
EpiControl
AF:
0.000296

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
Jun 13, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis suggests that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Alstrom syndrome Uncertain:3
Oct 18, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 690 of the ALMS1 protein (p.Thr690Ala). This variant is present in population databases (rs201804994, gnomAD 0.05%). 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: 240985). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant 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. -

Jan 24, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Mar 26, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Sep 30, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: ALMS1 c.2062A>G (p.Thr688Ala), alternate nomenclature p.Thr689Ala/p.Thr690Ala, results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00026 in 248908 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in ALMS1 causing Alstrom Syndrome (0.00026 vs 0.0014), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.2062A>G in individuals affected with Alstrom Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 240985). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Cardiovascular phenotype Benign:1
Apr 21, 2021
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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
0.13
BayesDel_addAF
Benign
-0.52
T
BayesDel_noAF
Benign
-0.64
CADD
Benign
15
DANN
Benign
0.96
DEOGEN2
Benign
0.038
T;.;.
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.3
FATHMM_MKL
Benign
0.039
N
LIST_S2
Benign
0.65
T;T;T
M_CAP
Benign
0.0048
T
MetaRNN
Benign
0.059
T;T;T
MetaSVM
Benign
-1.0
T
PhyloP100
-0.49
PrimateAI
Benign
0.30
T
Sift4G
Uncertain
0.043
D;D;T
Vest4
0.20
MVP
0.055
ClinPred
0.046
T
GERP RS
-8.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.043
gMVP
0.082
Mutation Taster
=96/4
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

Publications

Other links and lift over

dbSNP: rs201804994; hg19: chr2-73675719; COSMIC: COSV52518794; COSMIC: COSV52518794; API