Navigation Links
A nucleotide change could initiate fragile X syndrome
Date:9/1/2014

Researchers reveal how the alteration of a single nucleotidethe basic building block of DNAcould initiate fragile X syndrome, the most common inherited form of intellectual disability. The study appears in The Journal of Cell Biology.

Fragile X syndrome is caused by a defect in a gene on the X chromosome called fragile X mental retardation 1 (FMR1). Around 1 in 230 women and 1 in 360 men carry a so-called premutation, in which a series of DNA repeats at one end of the FMR1 gene is slightly longer than normal. These repeats are prone to even further expansion when FMR1 is passed from mother to child, causing the gene to switch off and stop producing a protein that is important for some cognitive functions.

A group of researchers from Albert Einstein College of Medicine of Yeshiva University in New York previously found that a certain site that initiates DNA replication, located near to the FMR1 gene, is inactivated in fragile X embryonic stem cells. This inactivation changes the way that the FMR1 gene is copied during cell division, which could pose problems that lead to expansion of the DNA repeats within the gene.

Intriguingly, a specific alteration in the DNA sequence near the FMR1 genea "single-nucleotide polymorphism" or SNP has been linked to an increased risk of repeat expansion in some premutation carriers. These researchers discovered that this SNP overlaps with the inactive replication origin in fragile X embryonic stem cells.

Nucleotides in DNA include one of four bases (cytosine, thymine, adenine, or guanine). The researchers found that normal embryonic stem cells had a thymine base at the SNP site and an active replication origin. Fragile X cells, in contrast, had a cytosine base and an inactive origin. The researchers also derived embryonic stem cells from mothers carrying the fragile X premutation. These cells had a thymine base and a normal replication pattern and, accordingly, showed no tendency to expand their repeat numbers over time.

The findings show that the substitution of cytosine for thymine might inactivate the DNA replication origin when the FMR1 gene is passed from mother to child, increasing the risk of DNA repeat expansions that can lead to fragile X syndrome.


'/>"/>

Contact: Rita Sullivan King
news@rupress.org
212-327-8603
Rockefeller University Press
Source:Eurekalert  

Related biology news :

1. Oligonucleotide Delivery: Biology, Engineering and Development Conference
2. Industry group release testing recommendations for oligonucleotide-based therapeutics
3. Splice-switching oligonucleotide therapeutics is new method for editing gene transcript
4. Holding a mirror to brain changes in autism
5. New study will help protect vulnerable birds from impacts of climate change
6. UNH researchers find African farmers need better climate change data to improve farming practices
7. Fielding questions about climate change
8. Glacier-fed river systems threatened by climate change
9. How old are these rocks, how were they made, and how long ago did these geologic changes happen?
10. Energy requirements make Antarctic fur seal pups vulnerable to climate change
11. Why spring is blooming marvelous (and climate change makes it earlier)
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
A nucleotide change could initiate fragile X syndrome
(Date:11/14/2016)... Nov. 14, 2016  Based on its ... Frost & Sullivan recognizes FST Biometrics with ... for Visionary Innovation Leadership. FST Biometrics emerged ... identification market by pioneering In Motion Identification ... instant, seamless, and non-invasive verification. This patented ...
(Date:6/22/2016)... June 22, 2016 On Monday, the Department ... industry to share solutions for the Biometric Exit Program. ... and Border Protection (CBP), explains that CBP intends to ... the United States , in order ... defeat imposters. Logo - http://photos.prnewswire.com/prnh/20160622/382209LOGO ...
(Date:6/15/2016)... 2016 Transparency Market Research ... Market by Application Market - Global Industry Analysis Size Share ... the report, the  global gesture recognition market  was ... is estimated to grow at a CAGR of ... Increasing application of gesture recognition technology ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... ... December 01, 2016 , ... ... findings demonstrating the value of DNA microarray comparative genomic hybridization (array CGH) ... Antonio Breast Cancer Symposium. Using molecular test results from tumors with previously ...
(Date:12/2/2016)... ... 01, 2016 , ... DrugDev believes the only way to achieve ... experience. All three tenets were on display at the 2nd Annual DrugDev User Summit ... sponsor, CRO and site organizations to discuss innovation and the future of clinical research. ...
(Date:12/2/2016)... , Dec. 1, 2016   SurePure, Inc. ... announced today that the Company has concluded an agreement ... right for a 90-day period to acquire units of ... of approximately USD 3.7 million.  Concurrently ... with Tamarack under which Tamarack will seek regulatory approvals ...
(Date:11/30/2016)...  GenomOncology today announced the appointment of Joshua F. ... Dr. Coleman will oversee clinical content development and ... The GenomOncology software suite empowers molecular pathologists with a seamless ... decision support, from quality control through reporting. ... , , ...
Breaking Biology Technology: