2-73419118-T-G

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS1

The NM_001378454.1(ALMS1):​c.451-5T>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000961 in 1,612,088 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000098 ( 0 hom. )

Consequence

ALMS1
NM_001378454.1 splice_region, intron

Scores

2

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts U:1B:4

Conservation

PhyloP100: 2.40

Publications

2 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: Benign. The variant received -16 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.74).
BP6
Variant 2-73419118-T-G is Benign according to our data. Variant chr2-73419118-T-G is described in ClinVar as Likely_benign. ClinVar VariationId is 529408.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.0000788 (12/152336) while in subpopulation EAS AF = 0.00231 (12/5184). AF 95% confidence interval is 0.00134. There are 0 homozygotes in GnomAd4. There are 6 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001378454.1. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ALMS1
NM_001378454.1
MANE Select
c.451-5T>G
splice_region intron
N/ANP_001365383.1
ALMS1
NM_015120.4
c.451-5T>G
splice_region intron
N/ANP_055935.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ALMS1
ENST00000613296.6
TSL:1 MANE Select
c.451-5T>G
splice_region intron
N/AENSP00000482968.1
ALMS1
ENST00000484298.5
TSL:1
c.325-5T>G
splice_region intron
N/AENSP00000478155.1
ALMS1
ENST00000614410.4
TSL:5
c.451-5T>G
splice_region intron
N/AENSP00000479094.1

Frequencies

GnomAD3 genomes
AF:
0.0000788
AC:
12
AN:
152218
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00231
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000141
AC:
35
AN:
248930
AF XY:
0.000178
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00189
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.0000980
AC:
143
AN:
1459752
Hom.:
0
Cov.:
31
AF XY:
0.000102
AC XY:
74
AN XY:
726286
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33440
American (AMR)
AF:
0.00
AC:
0
AN:
44704
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00343
AC:
136
AN:
39664
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86224
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53258
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1110248
Other (OTH)
AF:
0.000116
AC:
7
AN:
60328
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
10
21
31
42
52
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000788
AC:
12
AN:
152336
Hom.:
0
Cov.:
32
AF XY:
0.0000805
AC XY:
6
AN XY:
74512
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41576
American (AMR)
AF:
0.00
AC:
0
AN:
15312
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00231
AC:
12
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10632
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000434
Hom.:
0
Bravo
AF:
0.0000680
Asia WGS
AF:
0.000866
AC:
3
AN:
3478

ClinVar

Significance: Likely benign
Submissions summary: Uncertain:1Benign:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Alstrom syndrome Uncertain:1Benign:2
Jan 09, 2020
Natera, Inc.
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

Feb 04, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Feb 14, 2018
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.

not specified Benign:1
May 15, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: ALMS1 c.451-5T>G (also known as c.454-5T>G) alters a conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Several computational tools predict a significant impact on normal splicing: Two predict the variant abolishes a canonical 3' acceptor site and two predict the variant weakens the same canonical 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00014 in 248930 control chromosomes (gnomAD), predominantly at a frequency of 0.0019 within the East Asian subpopulation in the gnomAD database. The observed variant frequency within East Asian control individuals in the gnomAD database is approximately 1.3 fold of the estimated maximal expected allele frequency for a pathogenic variant in ALMS1 causing Alstrom Syndrome (0.0014), suggesting that the variant may be a benign polymorphism found primarily in populations of East Asian origin. c.451-5T>G has been reported in the literature in individuals affected with Alstrom Syndrome, retinitis pigmentosa and in an individual affected with combined 17 alpha hydroxylase/17,20-lyase deficiency without strong evidence of causality (Marshall_2015, Xu_2016, Zhang_2018). These reports do not provide unequivocal conclusions about association of the variant with Alstrom Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 25846608, 26010121, 29345162). Four ClinVar submitters have assessed the variant since 2014: two have classified the variant as uncertain significance and two as likely benign. Based on the evidence outlined above, the variant was classified as likely benign.

Cardiovascular phenotype Benign:1
May 27, 2023
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 v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.74
CADD
Benign
13
DANN
Benign
0.53
PhyloP100
2.4
PromoterAI
0.0028
Neutral
Mutation Taster
=4/96
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
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: rs774098604; hg19: chr2-73646246; API