Related Experiment Video
Updated: Aug 7, 2026
11:13
Using Mouse Oocytes to Assess Human Gene Function During Meiosis I
Published on: April 10, 2018
Summary
This study found elevated follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in individuals with trisomy 2, indicating impaired germinal and Leydig cell function. FSH measurement and testicular volume assessment are recommended for diagnosis.
Area of Science:
- Endocrinology
- Genetics
- Reproductive Medicine
Background:
- Trisomy 2 is associated with hypogonadism.
- Endocrine dysfunction in trisomy 2 requires further investigation.
Purpose of the Study:
- To evaluate the endocrinologic profile of patients with trisomy 2 and hypogonadism.
- To determine the diagnostic approach for germinal cell function in this population.
Main Methods:
- Endocrinologic evaluation of 39 patients with trisomy 2.
- Measurement of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and estradiol levels.
- Assessment of testicular volume in males.
Main Results:
- Elevated FSH and LH levels were observed, suggesting impaired germinal and Leydig cell function.
- A negative correlation between testicular size and FSH levels was found.
- Testosterone and estradiol levels were normal in males and females, respectively.
Conclusions:
- Germinal and Leydig cell functions are affected in trisomy 2.
- A simple diagnostic approach involves FSH measurement and testicular volume assessment in males.
Related Concept Videos
01:49Meiosis I
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by a...
01:29Nondisjunction
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.
03:09Meiosis I
Meiosis is the division of a diploid cell into haploid cells forming sperm and eggs in animals through differentiation. Meiosis I is the first stage of meiosis, where the genetic recombination of homologous chromosomes and the reduction of the ploidy level by half occurs.
Prophase I is the most extended and complex step of meiosis I characterized by synapsis, chromosome pairing, and recombination of the homologous chromosomes. This process is facilitated by a proteinaceous structure called the...
Prophase I is the most extended and complex step of meiosis I characterized by synapsis, chromosome pairing, and recombination of the homologous chromosomes. This process is facilitated by a proteinaceous structure called the...
01:29Nondisjunction
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.
01:21Nondisjunction
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...
01:24Gonadal and Placental Hormones
The gonads, namely the testes in males and the ovaries in females, are pivotal in producing gonadal hormones that orchestrate the intricate processes of sexual development and reproduction.
In males, testosterone is the primary gonadal androgen. It plays a central role in the maturation of male reproductive organs — the penis and testes. Additionally, testosterone is instrumental in the development of secondary sexual characteristics — a deep voice as well as facial and pubic hair growth — and...
In males, testosterone is the primary gonadal androgen. It plays a central role in the maturation of male reproductive organs — the penis and testes. Additionally, testosterone is instrumental in the development of secondary sexual characteristics — a deep voice as well as facial and pubic hair growth — and...