Turner Syndrome: Genotype and Phenotype - Clinical Tria...

Turner Syndrome: Genotype and Phenotype

Genetics Home Reference related topics: Turner syndrome
MedlinePlus related topics: Osteoporosis Turner Syndrome
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Study Type:Observational
Official Title:Turner Syndrome: Genotype and Phenotype

Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment:1200
Study Start Date:September 2000

Detailed Description:
Turner Syndrome (TS) is a sporadic disorder affecting approximately 1/2500 live female births. It is caused by the absence of all or significant parts of one sex-chromosome. Major developmental consequences include severe short stature, ovarian failure and distinctive cognitive and behavioral traits, with renal and cardiovascular defects affecting a minority. Adults with TS have excessive rates of osteoporosis, hypertension and diabetes mellitus and experience morbidity and mortality several-fold higher than the general population. Many of the problems of TS result from haplo-insufficiency for X-chromosome encoded genes, most of which remain unknown. Previous studies attempting to correlate genotype with phenotype in TS have been limited due to small numbers of subjects, limited genetic methodology and incomplete phenotypic characterization. This study aims to correlate TS phenotypes and genotypes using advanced clinical and genetic diagnostic methodologies, with the goal of identifying X-chromosome genes and epigenetic mechanisms causing the different features of TS. For TS subjects with a 45X genotype, the parental origin of the single normal X-chromosome will be traced to identify genomically imprinted features of the disorder. X chromosomal structural defects will be analyzed using high-resolution physical mapping in relation to emerging sequence data from the Human Genome Project. The elucidation of genetic mechanisms in TS will help improve the diagnosis and treatment of girls and women with this disorder and will further our understanding of gene dosage effects in general.

Eligibility
Ages Eligible for Study:10 Years and older
Genders Eligible for Study:Both
Accepts Healthy Volunteers:No
Criteria
INCLUSION CRITERIA - for TS Subjects:
Phenotypic females greater than or equal to 10 years of age

Evidence of X-chromosomal abnormality

Those with a karyotype of 45X/46XX must have at least 80% 45X lymphocytes.

EXCLUSION CRITERIA - for TS Subjects:

Co-existing autosomal defects

Pregnancy

INCLUSION CRITERIA - for the Parents of TS Subjects (for DNA only):

Biological parent of a TS subject

Willingness to participate

EXCLUSION CRITERIA - for the Parents of TS Subjects (for DNA only):

None

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00006334

Contacts
Contact: Patient Recruitment and Public Liaison Office (800) 411-1222 prpl@mail.cc.nih.gov
Contact: TTY 1-866-411-1010

Locations
United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike Recruiting
Bethesda, Maryland, United States, 20892

Sponsors and Collaborators
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
More Information

NIH Clinical Center Detailed Web Page

Publications:
Bakalov VK, Axelrod L, Baron J, Hanton L, Nelson LM, Reynolds JC, Hill S, Troendle J, Bondy CA. Selective reduction in cortical bone mineral density in turner syndrome independent of ovarian hormone deficiency. J Clin Endocrinol Metab. 2003 Dec;88(12):5717-22.
Hanton L, Axelrod L, Bakalov V, Bondy CA. The importance of estrogen replacement in young women with Turner syndrome. J Womens Health (Larchmt). 2003 Dec;12(10):971-7.
Bakalov VK, Chen ML, Baron J, Hanton LB, Reynolds JC, Stratakis CA, Axelrod LE, Bondy CA. Bone mineral density and fractures in Turner syndrome. Am J Med. 2003 Sep;115(4):259-64.

Publications indexed to this study:
Matura LA, Ho VB, Rosing DR, Bondy CA. Aortic dilatation and dissection in Turner syndrome. Circulation. 2007 Oct 9;116(15):1663-70. Epub 2007 Sep 17.

Study ID Numbers:000219, 00-CH-0219
First Received:October 4, 2000
Last Updated:December 11, 2008
ClinicalTrials.gov Identifier:NCT00006334 [history]
Health Authority:United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Genes
X-Chromosome
Osteoporosis
Ovarian Failure
Imprinting
Turner's
Turner
TS

Study placed in the following topic categories:
Chromosomal abnormalities
Genital dwarfism
Gonadal Disorders
Chromosome Disorders
Osteoporosis
Endocrine System Diseases
Ovarian Failure, Premature
Sex Differentiation Disorders
Monosomy X
Turner Syndrome
Gonadal dysgenesis
Urogenital Abnormalities
Genetic Diseases, Inborn
Turner syndrome
Ovarian dwarfism
Endocrinopathy
Congenital Abnormalities
Gonadal Dysgenesis

Additional relevant MeSH terms:
Pathologic Processes
Disease
Syndrome
Sex Chromosome Disorders