rs782518861

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_002025.4(AFF2):​c.926T>C​(p.Ile309Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000661 in 1,210,304 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 2 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000089 ( 0 hom., 0 hem., cov: 22)
Exomes 𝑓: 0.0000064 ( 0 hom. 2 hem. )

Consequence

AFF2
NM_002025.4 missense

Scores

3
14

Clinical Significance

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

Conservation

PhyloP100: 3.52

Publications

1 publications found
Variant links:
Genes affected
AFF2 (HGNC:3776): (ALF transcription elongation factor 2) This gene encodes a putative transcriptional activator that is a member of the AF4\FMR2 gene family. This gene is associated with the folate-sensitive fragile X E locus on chromosome X. A repeat polymorphism in the fragile X E locus results in silencing of this gene causing Fragile X E syndrome. Fragile X E syndrome is a form of nonsyndromic X-linked cognitive disability. In addition, this gene contains 6-25 GCC repeats that are expanded to >200 repeats in the disease state. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Jul 2016]
AFF2 Gene-Disease associations (from GenCC):
  • FRAXE intellectual disability
    Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)
  • non-syndromic X-linked intellectual disability
    Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.17219609).
BS2
High Hemizygotes in GnomAdExome4 at 2 XL gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AFF2NM_002025.4 linkc.926T>C p.Ile309Thr missense_variant Exon 3 of 21 ENST00000370460.7 NP_002016.2 P51816-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AFF2ENST00000370460.7 linkc.926T>C p.Ile309Thr missense_variant Exon 3 of 21 5 NM_002025.4 ENSP00000359489.2 P51816-1
AFF2ENST00000342251.7 linkc.914T>C p.Ile305Thr missense_variant Exon 3 of 20 1 ENSP00000345459.4 P51816-3
AFF2ENST00000370457.9 linkc.926T>C p.Ile309Thr missense_variant Exon 3 of 20 1 ENSP00000359486.6 P51816-6
AFF2ENST00000370458.5 linkc.914T>C p.Ile305Thr missense_variant Exon 3 of 8 1 ENSP00000359487.1 P51816-4

Frequencies

GnomAD3 genomes
AF:
0.00000892
AC:
1
AN:
112062
Hom.:
0
Cov.:
22
show subpopulations
Gnomad AFR
AF:
0.0000325
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000109
AC:
2
AN:
183009
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.0000760
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
0.00000637
AC:
7
AN:
1098242
Hom.:
0
Cov.:
32
AF XY:
0.00000550
AC XY:
2
AN XY:
363600
show subpopulations
African (AFR)
AF:
0.0000379
AC:
1
AN:
26403
American (AMR)
AF:
0.00
AC:
0
AN:
35207
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
19386
East Asian (EAS)
AF:
0.00
AC:
0
AN:
30206
South Asian (SAS)
AF:
0.0000185
AC:
1
AN:
54147
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
40534
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4137
European-Non Finnish (NFE)
AF:
0.00000594
AC:
5
AN:
842124
Other (OTH)
AF:
0.00
AC:
0
AN:
46098
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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:
0.00000892
AC:
1
AN:
112062
Hom.:
0
Cov.:
22
AF XY:
0.00
AC XY:
0
AN XY:
34238
show subpopulations
African (AFR)
AF:
0.0000325
AC:
1
AN:
30788
American (AMR)
AF:
0.00
AC:
0
AN:
10601
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
2650
East Asian (EAS)
AF:
0.00
AC:
0
AN:
3579
South Asian (SAS)
AF:
0.00
AC:
0
AN:
2686
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
6116
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
238
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
53204
Other (OTH)
AF:
0.00
AC:
0
AN:
1516
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.0000165
AC:
2

ClinVar

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

Submissions by phenotype

not provided Uncertain:2
Jan 11, 2016
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The I309T variant in the AFF2 gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The I309T variant was not observed in approximately 6500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The I309T variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position where amino acids with similar properties to Isoleucine are tolerated across species. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. We interpret I309T as a variant of uncertain significance. -

Nov 10, 2016
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.088
BayesDel_addAF
Benign
-0.094
T
BayesDel_noAF
Benign
-0.18
CADD
Benign
20
DANN
Uncertain
0.99
DEOGEN2
Benign
0.13
T;.;.;.
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Benign
0.76
T;T;T;T
M_CAP
Uncertain
0.22
D
MetaRNN
Benign
0.17
T;T;T;T
MetaSVM
Benign
-0.96
T
MutationAssessor
Benign
0.55
N;.;.;N
PhyloP100
3.5
PrimateAI
Benign
0.48
T
PROVEAN
Benign
-0.020
N;N;N;.
REVEL
Benign
0.18
Sift
Benign
0.57
T;T;T;.
Sift4G
Benign
0.50
T;T;T;T
Polyphen
0.24
B;B;B;B
Vest4
0.17
MutPred
0.34
Loss of stability (P = 0.0568);.;.;Loss of stability (P = 0.0568);
MVP
0.88
MPC
0.67
ClinPred
0.13
T
GERP RS
5.9
Varity_R
0.071
gMVP
0.16
Mutation Taster
=89/11
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: rs782518861; hg19: chrX-147744174; API