Skip to content
Medicines & Healthcare products Regulatory Agency
The National Institute for Biological Standards and Control

Confidence in biological medicines

  • Stay connected
  • Shopping Basket
  • Pay Now
  • Login / Register
  • Home
  • Products
  • Standardisation
  • Control testing
  • Science and research
  • Expert services
  • About us
  • Advanced therapies
  • Virology
  • Bacteriology
  • Biotherapeutics
  • Analytical sciences
  • Diagnostics
  • A to Z listing
  • Publications
  • Home  /  
  • Science and research  /  
  • Advanced therapies  /  
  • Genomic reference materials  /  
  • Fragile X (WHO)

Reference Panel for Fragile X Syndrome

Fragile X syndrome (OMIM #300624) affects approximately 1 in 3 000 males and 1 in 5 000 females.  

It is caused by the expansion of the number of CGG repeats in the 5’-untranslated region of the Fragile X mental retardation 1 (FMR1) gene with consequent hypermethylation of promotor regions and shutdown of gene expression. There are four categories of allelic forms of CGGn repeat length: 

  • normal: <50 repeats
  • intermediate (also referred to as ‘grey-zone’): 50-58 repeats
  • premutation: 59- approx. 200 repeats
  • full mutation > approx 200 repeats 

The panel consists of 5 genomic DNA samples:

  • normal female (consensus 22, 31 repeats)
  • premutation female (consensus 33, 113 repeats)
  • premutation male (consensus 114 repeats)
  • full mutation female (consensus 38, 346 repeats)
  • full mutation male (consensus 759 repeats)

Samples are presented as 23µg freeze dried genomic DNA in glass ampoules. The collaborative study indicates that these materials are suitable for use in Southern blot, PCR and Abbot PCR tests.

In addition, subsequent to the WHO collaborative study, the following data was obtained by two laboratories using the Asuragen PCR kit:

Assigned CGG repeat numbers (Hawkins et al, 2011)

Amplide X FMR1 PCR Kit results

NIBSC code

Description

Mean

Lab 1

Lab 2

07/120

Female, wild-type

22, 31

22, 31

22, 31

07/122

Female, premutation

33, 113

34,  105,116

34,  105,115

07/168

Female, full mutation

38, 346

39, >200

39, >200

07/170

Male, full mutation

754

>200

>200

07/174

Male, premutation

114

112, 119

112, 119

Reference

Hawkins M et al. (2011) Preparation and validation of the first WHO international genetic reference panel for Fragile X syndrome. Eur J Hum Genet. 19:10-7.

How to order

To place an order please login to your account or sign up for a new account. 

For scientific enquiries contact the team at grmteam@nibsc.org.

Key Staff

Dr Ross Hawkins – Section Head
Dr Ravneet Bhuller
Mr Malcolm Hawkins 
Dr Leandro Lo Cascio
Mr Noble Ossai
Dr Pia Sanzone
Mr Miltiades Stylianou

Available standards

08/158: WHO International Genetic Reference Panel for Fragile X Syndrome, Human DNA

Other genomic reference materials 

Ordering genomic reference materials

Further information on ordering genomic reference materials from NIBSC. 

Contact us 

grmteam@nibsc.org

  • Careers
  • Terms and conditions
  • Accessibility
  • Privacy notice
  • Cookies
  • Sitemap