Turner syndrome: new insights into an old disorder
1Department of Obstetrics and Gynecology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA. RSL1@PSU.EDU
Fertility and Sterility
|August 28, 2012
Abstract:
There have been marked advances in the understanding and treatment of Turner syndrome since its initial description in 1938. Greater knowledge of the heterogeneity of phenotypes, early treatment interventions with growth hormone and hormonal replacement, the risks of reproduction, spontaneous and assisted, and the long-term health of women with Turner syndrome has been achieved in the interim. But many perplexing ethical and clinical issues persist.
More Related Videos
Related Concept Videos
Sex Linked Disorders
Like autosomes, sex chromosomes contain a variety of genes necessary for normal body function. When a mutation in one of these genes results in biological deficits, the disorder is considered sex-linked.
Sex-linked Disorders
Like autosomes, sex chromosomes contain a variety of genes necessary for normal body function. When a mutation in one of these genes results in biological deficits, the disorder is considered sex-linked.
Nondisjunction
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
Nondisjunction
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold sister...
Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a neurodevelopmental condition marked by persistent deficits in social communication and interaction alongside restrictive and repetitive behaviors or interests. ASD is sometimes accompanied by intellectual impairment.
These core symptoms manifest differently among individuals, ranging from mild to severe. The disorder's complexity extends beyond its clinical presentation, encompassing a diverse range of biological, cognitive, and sociocultural influences.
These core symptoms manifest differently among individuals, ranging from mild to severe. The disorder's complexity extends beyond its clinical presentation, encompassing a diverse range of biological, cognitive, and sociocultural influences.
Meiosis vs. Mitosis
Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...


