X-linked recessive inheritance
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FRAXA syndrome

Fragile X Syndrome is the most common inherited cause of mental retardation, and is associated with autism. more...

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Causes

The fragile X syndrome is a genetic disorder caused by mutation of the FMR1 gene on the X chromosome. Mutation at that site is found in 1 out of about every 2000 males and 1 out of about every 4000 females.

Normally, the FMR1 gene contains between 6 and 53 repeats of the CGG codon (trinucleotide repeats). In people with the fragile X syndrome, the FMR1 allele has over 230 repeats of this codon.

Expansion of the CGG repeating codon to such a degree results in a methylation of that portion of the DNA, effectively silencing the expression of the FMR1 protein.

This methylation of the FMR1 locus in chromosome band Xq27.3 is believed to result in constriction and fragility of the X chromosome at that point, a phenomenon that gave the syndrome its name.

The mutation and methylation of the FMR1 gene lead to the transcriptional silencing of the fragile X-mental retardation protein, FMRP. In normal individuals, FMRP binds and facilitates the translation of a number of essential neuronal RNAs. In fragile X patients, however, these RNAs are not translated into proteins. The various sequelae of fragile X syndrome result.

Transmission of the Fragile X

The diagram (above) of X-linked recessive inheritance is not entirely inappropriate but it markedly oversimplifies the situation and does not provide a sufficient foundation for genetic counseling with the fragile X syndrome.

Because males normally have only one copy of the X chromosome, those males with significant trinucleotide expansion at the FMR1 locus are symptomatic. They are mentally retarded and may show various physical features of the fragile X syndrome.

Females have two X chromosomes and thus have double the chance of having a working FMR1 allele. Females carrying one X chromosome with an expanded FMR1 gene can have some signs and symptoms of the disorder or be normal.

Males with the fragile X cannot transmit it to any of their sons (since males contribute a Y chromosome, not an X, to their male offspring.)

Females carrying one copy of the fragile X can transmit it to their sons or daughters. Sons who receive the fragile X are at high risk for mental retardation. Daughters who receive the fragile X may appear normal or they may be mentally retarded, usually to a lesser degree than boys with the syndrome.

Symptoms

Aside from mental retardation, prominent characteristics of the syndrome include an elongated face, large or protruding ears, large testicles (macroorchidism), and low muscle tone. Behavioral characteristics may include stereotypic movements (e.g., hand-flapping) and atypical social development, particularly shyness and limited eye contact. Some individuals with the fragile X syndrome also meet the diagnostic criteria for autism.

Read more at Wikipedia.org


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Briefs: Horse trials voted area's best event+
From Daily Record (Rochester, NY), 2/8/02 by Scott Perkins

Here are some different events taking place around town.

Horse Trials

The Stuart Horse Trials have, again, been voted The Best Event in Area I for 2001.

This is the fifth time in 12 years the Olympic-style equestrian competition has received this prestigious honor. Riders, coaches and members of the United States Eventing Association vote on the recipient. Area I comprises New York and the five states of New England. There are 37 competitions in Area I.

This award is for over 400 volunteers who make this competition possible, noted Kyra King Stuart, competition organizer. It reflects the great community support we receive.

Stuart went on to say, People are learning this is a wonderful way to spend a weekend with your family ... to watch the exciting competition and enjoy the beautiful Victor countryside. Our attendance tripled last year as people are learning of this important happening in July.

$10,000 Donation By Board Of Directors

Some $10,000 in donations for the year 2001 have been approved for distribution according to an announcement by Stuart Horse Trials' Board of Directors.

Among the beneficiaries of this gifting are Western New York Region, United States Pony Clubs, Inc., for educational riding clinics for regional members; Fraxa Research Foundation for Fragile X Syndrome, a genetic disorder affecting one in 2,000 boys and one in 400 girls with a wide range of mental and physical impairments; the Victor-Farmington Volunteer Ambulance Corp.; Mercy Flight Central; East Bloomfield Ambulance; the Humane Society at Lollypop Farm; and the Ontario County Sheriff's Office.

The next Stuart Horse Trials will take place July 26-28, 2002.

Grieving Pet Owners

In an effort to assist individuals or families grieving the loss of a beloved pet, the Humane Society at Lollypop Farm will offer Getting Through The Grief: Living With Pet Loss, February 9 at 1 p.m. at the Humane Society shelter, 99 Victor Rd., Fairport.

Laurie McGrath, a rehabilitation therapist with experience in grief counseling, will facilitate the program.

Pets provide some of the happiest moments of our lives, McGrath said. They serve as devoted companions, giving us their unconditional love and acceptance. Upon the death of a pet, many owners experience intense sadness and feelings of loss. We hope this program will provide grieving pet owners with coping tools that might help to ease their pain.

Participants will learn about the different stages of grief and how they may work through their feelings of grief, guilt and loss. This will be accomplished in a non-judgmental environment in the company of others who have suffered a similar loss.

The seminar is free to those who wish to attend, but seating is limited. Call 223-1330, ext. 251 or register online at www.lollypop.org to reserve a seat.

If you have a candidate for Going The Extra Mile, please contact Scott Perkins at 394-3343. His e-mail is sperkins@frontiernet.net. Perkins is CEO of Agility Advertising Agency, 80 North Union St., Rochester, NY 14607.

Copyright 2002 Dolan Media Newswires
Provided by ProQuest Information and Learning Company. All rights Reserved.

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