Description, Causes and Risk Factors:
Swyer syndrome is also knowns as gonadal dysgenesis is characterized by "streak gonads" is a phenotypic female with a 46,XY karyotype. This condition is due to a mutation which inhibits the function of the Y-borne determinant that would normally cause the indifferent embryonic gonad to differentiate into a testis. The streak gonad is incapable of ovulation or estrogen secretion. The syndrome is sometimes called "pure gonadal dysgenesis," however, this designation may also refer to the presence of streak gonads with a 46,XX karyotype. Mixed gonadal dysgenesis has extreme variability, which may extend from a Turner-like syndrome to a male phenotype.
The etiology of 46 XY gonadal dysgenesis is though to be a short arm Y chromosome deletion involving SRY, a mutation in other genes that leads to inhibition of SRY function or mutation of SRY function. To date, 20% of 46 XY pure gonad dysgenesia are explained by a mutation or a deletion in SRY. In 80%, SRY is apparently normal. A female patient with an XY Karyotype who has a Palpable mullerian system, normal female testosterone levels, and lack of sexual development has Swyer syndrome, Tumor transformation in the gonadal ridge can occur at any age.
Mixed gonadal dysgenesis that primary amenorrhea is associated with various mosaic status, the most common of which is 45X/46xx. When compared to the pure 45X cell line, individuals with 45X/46XX are taller and have fewer abnormalities. Spontaneous menstruation occurs in approximately 20% of these patients.
Partial gonadal dysgenesis. They have karyotype 46XX with part of one of the X chromosomes missing. The phenotype is variable depending on the amount and location of the missing genetic material. In 46 XY partial gonadal dysgenesis individuals there is some testicular development; therefore they present as newborns with ambiguous genitalia.
Complete or pure gonadal dysgenesis. The patients are phenotypic females with a 46 XY karyotype and hypoplastic gonads without germ cells. They present most often with primary amenorrhea with normal stature. The gonads are usually streaks, but there may be some development of secondary sexual characteristics as well as a few episodes of uterine bleeding.
The patients with Swyer syndrome patients arediagnosed in early adolescence with delayed pubertaldevelopment. As expected they show elevated gonadotropins (hormone secreted by the anterior pituitary gland and placenta; stimulates the gonads and controls reproductive activity), normal female levels of androgens and low levels ofestrogens, female external genitalia, uterus and fallopiantubes. Minimal breast enlargement reflects peripheral aromatization of androgens. Menstrual function suggeststumor development in the streak gonad. These streaksoften display ovarian stroma but no follicles.
X-linked recessive inheritance.
In females with delayed puberty, a pelvic ultrasound can be performed to confirm the presence or absence of ovaries.Additionally, blood can be taken for a karyogram, which identifies the full set of chromosomes of the female. Females with Swyer syndrome will have both X and Y chromosomes rather than a set of two X chromosomes, which is normal for females.
Symptoms of Swyer syndrome can be treated with hormone replacement therapy (HRT), although surgical procedures are not uncommon. A typical HRT regimen includes estrogen and progesterone treatment to regulate menstruation and induce the female's secondary sexual characteristics. In some cases, the fibrous streak gonads are surgically removed as a precautionary measure against the development of gonadoblastomas a type of cancer of the gonads.
NOTE: The above information is for processing purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.
Here is the list of nine user-friendly gym machines for women that are intimidated by barbells, bumper plates, and squat racks by Robin Cortez, director of team training for Chuze Fitness, which has clubs in California, Colorado and Arizona: Smith machine — used for...
A new study from Imperial College London suggests that higher levels of iron may cut the risk of clogged arteries. On the other hand, they are linked to a higher risk of blood clots. Within the scope of the study, the scientists used genetic data from 500,000 people...
When it is so hot outside you still can find hundreds of ways to cool yourself and drinking a mocktail is one of them. Here are few wonderful recipes for you to try. Kiwi Sour 1 oz orange juice 3 slices kiwi 0.75 oz demerara green tea syrup 0.75 oz lime juice 1 oz...read more
Many people are motivated for active sports in spring. However, before you buy a membership, you should check which exercises are useful to you and which ones should not be done in any way. Unfortunately, nowadays there are practically no people with an absolutely...read more
In childhood, many of us dreamed of learning to jump high. Now, after years, it became easier - Kangoo Jumps has appeared. This is one of the relatively new, but quickly gaining popularity types of fitness training. There are several advantages of jumpers. ...read more