FRAXE AFF2

Disease ID
FRAXE
Gene ID
AFF2

Disease

Name
Fragile X syndrome, FRAXE type
Inheritance
X-linked recessive
Description
A nonsyndromic X-linked mental retardation (NS-XLMR) characterized by mild intellectual deficit. FRAXE is the most common form of NS-XLMR1 .
Prevalence
2 50,000
1-4/100,000 males2 ; 1/50-100,000 males, more than 50 families3 . Found in populations around the globe, including in the UK, US, Canada, Taiwan, Germany, Greece, Cyprus, Spain, and Finland3 .
Age of Onset(Typical)Years1  102  10
Age of Onset Details
Typical: 2-103 . Range: 1-10; developmental delays without physical features can make onset difficult to detect until schooling4 .

Locus

Details
Allele ranges (benign:4-39; pathogenic: >200) inferred from The Human Gene Mutation Database5 . Intermediate alleles correspond to a premutation6 . Non-canonical motifs include: CGG/CCT/GTG/CAG/CTG37,8 .
Mechanism
LoF
Loss of function via transcriptional silencing9,10 .
Year
199311
Gene Strand

Alleles

Ref. Motif
GCC
Pathogenic (ref.)
GCC
Pathogenic (gene)
CCG
BenignIntermediatePathogenicUnits4  3940  200201  2,000

References

Direct supporting references for info on this page.

1
Ontology Lookup Service (OLS)
mondo:0010659
2
Fragile XE syndrome: MedlinePlus Genetics
url:medlineplus.gov/genetics/condition/fragile-xe-syndrome
3
The FMR2 gene, FRAXE and non-specific X-linked mental retardation: clinical and molecular aspects.
J,Gecz
Annals of human genetics · 2000-03-01
pmid:11246464
5
Resources for Genetics Professionals — Genetic Disorders Caused by Nucleotide Repeat Expansions and Contractions
Stephanie E.,Wallace, Lora JH,Bean
GeneReviews® [Internet] · 2022-10-20
genereviews:NBK535148
6
Development and validation of a multiplex-PCR assay for X-linked intellectual disability.
Paula,Jorge, Bárbara,Oliveira, Isabel,Marques, Rosário,Santos
BMC medical genetics · 2013-08-05
pmid:23914978
7
Comprehensive genetic diagnosis of tandem repeat expansion disorders with programmable targeted nanopore sequencing.
Igor,Stevanovski, Sanjog R,Chintalaphani, Hasindu,Gamaarachchi, James M,Ferguson, Sandy S,Pineda, Carolin K,Scriba, Michel,Tchan, Victor,Fung, Karl,Ng, Andrea,Cortese, Henry,Houlden, Carol,Dobson-Stone, Lauren,Fitzpatrick, Glenda,Halliday, Gianina,Ravenscroft, Mark R,Davis, Nigel G,Laing, Avi,Fellner, Marina,Kennerson, Kishore R,Kumar, Ira W,Deveson
Science advances · 2022-03-04
pmid:35245110
8
Simultaneous Screening of the FRAXA and FRAXE Loci for Rapid Detection of FMR1 CGG and/or AFF2 CCG Repeat Expansions by Triplet-Primed PCR.
Timing,Liu, Furene S,Wang, Felicia S H,Cheah, Yanghong,Gu, Marie,Shaw, Hai-Yang,Law, Stacey K H,Tay, Caroline G,Lee, David L,Nelson, Jozef,Gecz, Samuel S,Chong
The Journal of molecular diagnostics : JMD · 2021-06-07
pmid:34111553
9
Diseases of unstable repeat expansion: mechanisms and common principles.
Jennifer R,Gatchel, Huda Y,Zoghbi
Nature reviews. Genetics · 2005-10-01
pmid:16205714
10
Clinical and neuroimaging review of triplet repeat diseases.
Ryo,Kurokawa, Mariko,Kurokawa, Akihiko,Mitsutake, Moto,Nakaya, Akira,Baba, Yasuhiro,Nakata, Toshio,Moritani, Osamu,Abe
Japanese journal of radiology · 2022-09-28
pmid:36169768
11
Trinucleotide repeat amplification and hypermethylation of a CpG island in FRAXE mental retardation.
S J,Knight, A V,Flannery, M C,Hirst, L,Campbell, Z,Christodoulou, S R,Phelps, J,Pointon, H R,Middleton-Price, A,Barnicoat, M E,Pembrey
Cell · 1993-07-16
pmid:8334699

Additional Literature

Additional literature related to this locus.

Raw PubMed search results
(All PubMed results returned by searching for this gene, tandem repeats, and disease, in medline format)

Dongfang,Zou, Bing,Qin, Jie,Wang, Yiwu,Shi, Peng,Zhou, Yonghong,Yi, Jianxiang,Liao, Xinguo,Lu
Frontiers in molecular neuroscience · 2022-03-30
pmid:35431806
Distribution of FMR1 and FMR2 Repeats in Argentinean Patients with Primary Ovarian Insufficiency.
Lucía Daniela,Espeche, Violeta,Chiauzzi, Ianina,Ferder, Mehrnoosh,Arrar, Andrea Paula,Solari, Carlos David,Bruque, Marisol,Delea, Susana,Belli, Cecilia Soledad,Fernández, Noemí Delia,Buzzalino, Eduardo Hernán,Charreau, Liliana Beatriz,Dain
Genes · 2017-08-16
pmid:28812997
Point mutation frequency in the FMR1 gene as revealed by fragile X syndrome screening.
Maximilian,Handt, Andrea,Epplen, Sabine,Hoffjan, Kemal,Mese, Jörg T,Epplen, Gabriele,Dekomien
Molecular and cellular probes · 2014-08-27
pmid:25171808
FRA2A is a CGG repeat expansion associated with silencing of AFF3.
Sofie,Metsu, Liesbeth,Rooms, Jacqueline,Rainger, Martin S,Taylor, Hemant,Bengani, David I,Wilson, Chandra Sekhar Reddy,Chilamakuri, Harris,Morrison, Geert,Vandeweyer, Edwin,Reyniers, Evelyn,Douglas, Geoffrey,Thompson, Eric,Haan, Jozef,Gecz, David R,Fitzpatrick, R Frank,Kooy
PLoS genetics · 2014-04-24
pmid:24763282
Crystallographic characterization of CCG repeats.
Agnieszka,Kiliszek, Ryszard,Kierzek, Wlodzimierz J,Krzyzosiak, Wojciech,Rypniewski
Nucleic acids research · 2012-06-19
pmid:22718980
Familial intellectual disability and autistic behavior caused by a small FMR2 gene deletion.
Georg M,Stettner, Moneef,Shoukier, Christoph,Höger, Knut,Brockmann, Bernd,Auber
American journal of medical genetics. Part A · 2011-07-07
pmid:21739600
Distribution of CGG/GCC repeats at the FMR1 and FMR2 genes in an Indian population with mental retardation of unknown etiology.
Lavanya,Katikala, Mallikarjuna R,Guruju, Sujatha,Madireddi, Omsairamesh,Vallamkonda, Nagaratna,Vallamkonda, Amarjyothi,Persha, Anandaraj M P J,Spurgeon
Genetic testing and molecular biomarkers · 2011-01-23
pmid:21254876
Determinants of R-loop formation at convergent bidirectionally transcribed trinucleotide repeats.
Kaalak,Reddy, Mandy,Tam, Richard P,Bowater, Miriam,Barber, Matthew,Tomlinson, Kerrie,Nichol Edamura, Yuh-Hwa,Wang, Christopher E,Pearson
Nucleic acids research · 2010-11-04
pmid:21051337
Argonaute-2-dependent rescue of a Drosophila model of FXTAS by FRAXE premutation repeat.
Oyinkan A,Sofola, Peng,Jin, Juan,Botas, David L,Nelson
Human molecular genetics · 2007-07-17
pmid:17635840