publicado em 30/05/2012 às 19h10:00
   Dê o seu voto:

Scientists discover gene that causes a rare syndrome that inhibits the growth

Research has revealed hitherto unknown molecular mechanism. Discovery can be useful for the understanding of diseases

font size

Some pieces of information on this page may have been automatically translated. Makernews is not responsible for the irregularities resulting from these translations. When in doubt,      consult the original text.

A study by an international group of scientists with Brazilian participation, identified the gene that causes the syndrome IMAGE, English acronym for intrauterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenita and genital anomalies. IMAGE Syndrome carriers, whose cause was unknown until now, generally have low birth weight, impaired development of the adrenal glands, skeletal changes and genitals. The study results published in the journal Nature Genetics.

According to the authors, the survey revealed a previously unknown molecular mechanism. Although this is an extremely rare genetic syndrome, the discovery could be useful for understanding the most prevalent diseases.

According to a study author, Bruno Ferraz-de-Souza, a researcher at the Faculty of Medicine, University of São Paulo (USP), CDKN1C mutations had been described as another cause of much more frequent syndrome, characterized by overgrowth. In the new study, scientists found that the gene is also responsible for the syndrome Image, which involves the growth restriction.

Many years have sought the cause of the syndrome IMAGE. In this work, using parallel sequencing - analyzing DNA samples from an Argentine family with many affected members and other samples of patients collected over the past 20 years - we find that the syndrome is caused by a specific mutation in the CDKN1C gene, on chromosome 11 said Ferraz-de-Souza Agency FAPESP.

The study included scientists from the University of California at Los Angeles (United States), University College London (UK) and the Hospital de Niños Ricardo Gutierrez (Argentina).

According Ferraz-of-Souza, it was known that the CDKN1C played an important role in the regulation of cell growth. Mutations in the gene had been associated with Beckwith-Wiedemann syndrome, which causes abnormal growth of body parts and organs, exacerbating the risk of appearance of tumors.

Now we know that the same gene that causes overgrowth syndrome is also responsible for this syndrome rarest hipocrescimento said.

However, the changes that were found in Beckwith-Wiedemann syndrome are scattered across all regions of this gene. Since the mutations that cause the syndrome IMAGE occur in a region very limited, with only six amino acids. A simple change of position in this region determines completely different phenotypes, said Ferraz-de-Souza.

A genetic factor complex has the further discovery, gene expression is controlled by imprinting CDKN1C thus the disease manifests itself only when the maternally inherited. The person who has the mutation inherited from the father does not have the disease, although it may pass the mutation to their children.

The mechanism by which this mutation occurs in the six amino acids that cause the disease remains unknown. But it is possible that the mechanism are valid for study, for example, tumorigenesis, and other forms of genetic defects that lead to cancer. The findings on mechanisms of rare diseases may be relevant when transported to the most prevalent diseases, said Ferraz-de-Souza.

The first part of the study was based on the analysis of DNA from a family from Argentina who had at least four generations of individuals affected and unaffected by the syndrome. The samples from this family, the scientists of the U.S. team did SNP arrays to define the chromosomal region where the gene was probably predisposes to the disease and began to apply techniques for parallel sequencing.

After studying the Argentine family, was suspected that the cause gene mutations in CDKN1C. In such cases it is the practice find other individuals with the same phenotype in order to confirm that it is certain gene, said Ferraz-of-Souza.

At the time of the study, the scientist who was studying PhD at University College London, trying to find the genes that caused an adrenal disease.

In England, we had some DNA samples from patients with the phenotype that the U.S. group was seeking. They contacted us and confirmed that the mutation occurred always in the same six amino acids, he said.

Since abortion is legal in the UK, the British team of researchers had access to fetal material. Thus, it was possible to demonstrate, by immunohistochemistry and by quantitative PCR, the gene was indeed expressed in the adrenal gland during normal development. It is possible that the gene CDKN1C is very important for normal growth of the adrenal said.

Other diseases <b> </ b>

At the end of the study, scientists have functional studies to show that the change in the gene actually causes changes in the phenotype.

We did experiments with fruit flies. The introduction of mutations in this gene led flies to submit a drastic reduction in size of the eyes and wings. It was confirmed that the changes in that exact position of the gene led to growth failure, said Ferraz-de-Souza.

He said he still remains to be seen that changes in so small a portion of DNA mutations lead to such grave. This is a very interesting field of research, this may lead to understanding that similar mechanisms may be involved in other diseases hipocrescimento said.

Back in Brazil, Ferraz-de-Souza conducts studies on defects in the vitamin D receptor and skeletal diseases, with support from FAPESP through the Young Scholars Program in Emerging Centers.

Although it is a different line of research, it is possible that we can collaborate in continuing research on the IMAGE syndrome, since the skeletal changes are part of its manifestations, he said.

Veja aqui o artigo sobre o estudo.

   Palavras-chave:   IMAGE syndrome    A rare syndrome    Intrauterine growth    Metaphyseal dysplasia    Gene    Genetics    Molecular mechanism   
  • Share this pageShare this page
  • Share this pageCorrect
  • ShareShare
  • AlertAlert
Reduced link: 
  • You are recommending this story: Scientists discover gene that causes a rare syndrome that inhibits the growth
  • Fill in the following form to send your recommendation to your friend:

  • You are suggesting a correction for this story: Scientists discover gene that causes a rare syndrome that inhibits the growth

Receba notícias do iSaúde no seu e-mail de acordo com os assuntos de seu interesse.
Seu nome:
Seu email:
Desejo receber um alerta com estes assuntos:
IMAGE syndrome    a rare syndrome    intrauterine growth    metaphyseal dysplasia    gene    genetics    molecular mechanism   
Leave your comment
(Required fields are marked with an *)

(Your email address will never be published or shared.)

Enter the letters and numbers below and click in the button "send"

  • Twitter iSaúde
Informe Saúde printed version

Recommend the portal
Close [X]
  • You are recommending this story:
  • Fill in the following form to send your recommendation to your friend:

RSS news from the portal  iSaú
Get the newsletter of the portal  iSaú
Recommend the portal iSaú
News from  iSaú in your blog or website.
Get news on the subject of your interest.
© 2000-2011 Todos os direitos reservados.