rs577076002

Variant summary

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

The NM_173630.4(RTTN):​c.998C>T​(p.Ala333Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000484 in 1,609,978 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A333A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000049 ( 0 hom. )

Consequence

RTTN
NM_173630.4 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.17

Publications

1 publications found
Variant links:
Genes affected
RTTN (HGNC:18654): (rotatin) This gene encodes a large protein whose specific function is unknown. Absence of the orthologous protein in mouse results in embryonic lethality with deficient axial rotation, abnormal differentiation of the neural tube, and randomized looping of the heart tube during development. In human, mutations in this gene are associated with polymicrogyria with seizures. In human fibroblasts this protein localizes at the ciliary basal bodies. Given the intracellular localization of this protein and the phenotypic effects of mutations, this gene is suspected of playing a role in the maintenance of normal ciliary structure which in turn effects the developmental process of left-right organ specification, axial rotation, and perhaps notochord development. [provided by RefSeq, Jan 2013]
RTTN Gene-Disease associations (from GenCC):
  • microcephalic primordial dwarfism due to RTTN deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae)
  • bilateral generalized polymicrogyria
    Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

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=0.006293744).
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.0000395 (6/151960) while in subpopulation SAS AF = 0.00104 (5/4812). AF 95% confidence interval is 0.000409. There are 0 homozygotes in GnomAd4. There are 3 alleles in the male GnomAd4 subpopulation. Median coverage is 31. 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
RTTNNM_173630.4 linkc.998C>T p.Ala333Val missense_variant Exon 8 of 49 ENST00000640769.2 NP_775901.3 Q86VV8-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
RTTNENST00000640769.2 linkc.998C>T p.Ala333Val missense_variant Exon 8 of 49 2 NM_173630.4 ENSP00000491507.1 Q86VV8-1

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
151854
Hom.:
0
Cov.:
31
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:
0.00
Gnomad SAS
AF:
0.00104
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000814
AC:
20
AN:
245704
AF XY:
0.000112
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000880
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000180
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000494
AC:
72
AN:
1458018
Hom.:
0
Cov.:
31
AF XY:
0.0000607
AC XY:
44
AN XY:
725308
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33054
American (AMR)
AF:
0.0000677
AC:
3
AN:
44296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26002
East Asian (EAS)
AF:
0.0000254
AC:
1
AN:
39332
South Asian (SAS)
AF:
0.000465
AC:
40
AN:
85990
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53340
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5744
European-Non Finnish (NFE)
AF:
0.0000252
AC:
28
AN:
1110032
Other (OTH)
AF:
0.00
AC:
0
AN:
60228
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.468
Heterozygous variant carriers
0
4
7
11
14
18
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:
0.0000395
AC:
6
AN:
151960
Hom.:
0
Cov.:
31
AF XY:
0.0000404
AC XY:
3
AN XY:
74252
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15252
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00104
AC:
5
AN:
4812
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10522
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67972
Other (OTH)
AF:
0.00
AC:
0
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
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:
0.0000450
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.0000910
AC:
11

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Apr 30, 2015
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Jul 30, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ClinVar contains an entry for this variant (Variation ID: 212087). This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 333 of the RTTN protein (p.Ala333Val). This variant is present in population databases (rs577076002, gnomAD 0.05%). This variant has not been reported in the literature in individuals affected with RTTN-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.058
BayesDel_addAF
Benign
-0.48
T
BayesDel_noAF
Benign
-0.59
CADD
Benign
11
DANN
Benign
0.90
DEOGEN2
Benign
0.050
T;.;.
Eigen
Benign
-1.1
Eigen_PC
Benign
-0.91
FATHMM_MKL
Benign
0.14
N
LIST_S2
Benign
0.43
T;T;T
M_CAP
Benign
0.0079
T
MetaRNN
Benign
0.0063
T;T;T
MetaSVM
Benign
-0.99
T
MutationAssessor
Benign
-1.4
N;N;.
PhyloP100
1.2
PrimateAI
Benign
0.37
T
PROVEAN
Benign
-0.29
.;N;.
REVEL
Benign
0.068
Sift
Benign
0.60
.;T;.
Sift4G
Benign
0.47
.;T;.
Polyphen
0.0020
B;.;.
Vest4
0.25
MutPred
0.15
Gain of sheet (P = 0.0101);Gain of sheet (P = 0.0101);.;
MVP
0.085
MPC
0.070
ClinPred
0.028
T
GERP RS
2.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.034
gMVP
0.34
Mutation Taster
=94/6
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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: rs577076002; hg19: chr18-67860533; API