What Is Complete Gonadal Dysgenesis?
Complete gonadal dysgenesis is a hereditary condition in which the gonads or the reproductive organs are replaced by fibrous tissue. The gonads are the organs responsible for the reproductive functions of males and females. The gonads are present in both males and females. In males, the testes or the testicles are responsible for carrying out the reproductive function, whereas, in females, the ovaries are the reproductive organs.
Normally, the gonads form even before the baby is born, giving rise to testicles and ovaries in males and females. However, the problem arises when these gonads fail or incompletely develop. This condition is known as complete gonadal dysgenesis.
What Are the Different Types of Gonadal Dysgenesis?
Gonadal dysgenesis can be classified into different types depending on the morphology (external appearance) of gonads and the number and appearance of chromosomes. The human body contains millions of cells, each containing a nucleus. The nucleus is a structure that contains chromosomes responsible for storing the body's genetic information. There are 22 pairs of autosomes and a pair of sex chromosomes. The sex chromosomes are represented as X and Y. The females usually inherit two X chromosomes, and the males inherit one X and one Y chromosome.
The different types of gonadal dysgenesis based on gonadal morphology are listed in the table below:
What Are the Causes of Gonadal Dysgenesis?
Gonadal dysgenesis occurs when the gonads fail to develop properly. As a result, the male and the female sex organs are either absent or replaced by fibrous tissues. The different causes of gonadal dysgenesis are listed below:
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Hormonal Disturbances - Anti-mullerian hormone and testosterone hormones are mainly responsible for complete gonadal dysgenesis. These hormones are responsible for the stabilization of the Wolffian duct. It is a paired organ present in humans that gives rise to the male reproductive organs. When the hormones are missing, the Wolffian duct fails to develop. As a result, the individual processes female-like features resulting in gonadal dysgenesis.
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Genetic Defects - The sex-determining region of the Y chromosome (SRY) gene is responsible for the formation of male sex organs, that is, the testis. These genes are responsible for the growth and differentiation of the testicles. However, the problem arises when this gene is defective. As a result, the testicles fail to develop, and the person lacks testosterone and anti-Mullerian hormones. When there is no anti-mullerian hormone, the Mullerian ducts form the female sex organs like the uterus, vagina, and cervix. The testis and ovaries are replaced by fibrous tissue, and the condition is known as streak gonads.
What Are the Signs and Symptoms of Complete Gonadal Dysgenesis?
The signs of gonadal dysgenesis vary according to the sex of a person. However, the following signs and symptoms are commonly seen in gonadal dysgenesis:
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Short stature.
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Underdeveloped penis and testes.
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Normally, boys hit puberty between ten to 14 years of age. However, the one who lacks gonads experience delayed puberty.
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Infertility or the inability to become a father.
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Absence of menstruation in girls.
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Low energy levels.
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Sex drive is low or absent.
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Boys undergo certain changes during puberty, including the growth of hairs in the pubic region, deepening of the voice, and increase in muscle strength. Patients suffering from complete gonadal dysgenesis usually lack these secondary sexual changes.
What Tests Are Done to Diagnose Complete Gonadal Dysgenesis?
Complete gonadal dysgenesis can be diagnosed on the basis of a karyotype test and pelvic imaging test. The diagnostic methods are described below:
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Karyotype Test - A karyotype test looks at the size, shape, and number of chromosomes. This test is usually indicated in both babies and young children to look at the defects in the chromosomes. There are two ways to obtain samples for a karyotype test. The doctor might take a blood sample by injecting the needle into the veins, or he might inject the needle into the abdomen to take a sample of amniotic fluid. The sample obtained is then examined in the laboratory. Any change in the number and structure of chromosomes indicates a disorder. So, this test is especially helpful in diagnosing chromosomal disorders even before the baby is born.
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Pelvic Ultrasound - Pelvis is a structure present in the human body that supports the abdominal and genital organs. Pelvic ultrasound is a type of imaging test in which sound waves are sent to the body's organs with the help of a device known as a transducer. The advantage of this procedure is that the person is not exposed to X-ray radiation. The doctor moves the transducer at different angles to obtain images of the pelvic organs. Streak gonads or abnormalities in the testes and ovaries can be easily seen with the help of ultrasound.
How to Manage Complete Gonadal Dysgenesis?
Complete gonadal dysgenesis is a condition in which the gonads have failed to develop due to genetic defects or changes in hormone levels. The treatment options have been described below:
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Hormone Replacement Therapy (HRT) - After the patient has been diagnosed with complete gonadal dysgenesis, estrogen and progesterone hormone therapy are usually started. These hormones allow the development of normal sexual characteristics to avoid complications. Estrogen replacement therapy is especially useful for a woman who wants to undergo assisted reproductive procedures like in vitro fertilization (IVF). Also, estrogen promotes the development of breasts and hips in females with gonadal dysgenesis. Growth hormone can be injected into children showing delayed growth.
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Gonadectomy - It is a procedure in which the gonads (testes or ovaries) are surgically removed. This procedure is mainly done when there is a risk of malignancy or cancer due to gonadal dysgenesis. If the parents want to raise the child as a female, the testicles are removed. On the contrary, if the child has to be brought up as a male, the female reproductive organs (ovaries) are removed.
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Assisted Reproductive Technique (ART) - Patients suffering from gonadal dysgenesis cannot produce their own sperm or eggs. In such a situation, assisted reproductive procedures like in vitro fertilization, surrogacy, fertility medications, and artificial insemination can be used to become a parent. If a woman cannot carry the baby or produce eggs, she can use the option of surrogacy to become a mother.
What Are the Complications of Gonadal Dysgenesis?
When the gonads fail to develop, the patient faces severe problems, remains depressed, and considers himself inferior to society. The complications of gonadal dysgenesis are listed below:
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Gonadoblastoma - It is one of the most serious complications of gonadal dysgenesis. Gonadoblastoma or germ cell tumor occurs when the cells in the gonads show uncontrolled growth. It is mostly benign but might turn cancerous later in life.
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Infertility - Infertility is the inability of a person to become a parent. As the gonads have not developed properly, the patient cannot produce eggs and sperm. Failure of the person to produce sperm or eggs leads to infertility.
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Ambiguous Genitalia - It is a condition in which the baby is born with the reproductive organs of both sexes. It becomes difficult to recognize whether the baby is a boy or a girl.
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Stillbirth - When the baby dies before or during the delivery, it is known as a stillbirth. Patients suffering from complete gonadal dysgenesis are more likely to have stillbirths because they cannot carry the baby due to the absence of gonads.
Conclusion:
Complete gonadal dysgenesis is a condition in which the testicles and the ovaries fail to develop. Genetic defects and changes in hormone levels are the main causes of gonadal dysgenesis. A karyotype test and pelvic ultrasound can diagnose the condition. Infertility is the biggest issue that is associated with gonadal dysgenesis. However, the patient needs not worry as assisted reproductive procedures are available to help them become parents. Consult the doctor immediately to learn about gonadal dysgenesis and its treatment options.
