What is the Difference Between XXY and XYY Syndrome

Aneuploidy is a genetic disorder where total chromosomes are not equal to 46. There are two main types of aneuploidy: trisomy (having extra chromosome; 47) and monosomy (missing a chromosome; 45). XXY and XYY syndrome are two aneuploidy disorders in males due to an extra copy of chromosome in the cells.

The key difference between XXY and XYY syndrome is the type of extra chromosome present. In XXY syndrome, a male has an extra copy of the X chromosome in each of their cells, while in XYY syndrome, a male has an extra copy of the Y chromosome in each of their cells.

CONTENTS

1. Overview and Key Difference
2. What is XXY Syndrome
3. What is XYY Syndrome
4. Similarities – XXY and XYY Syndrome
5. XXY vs XYY Syndrome in Tabular Form
6. Summary – XXY vs XYY Syndrome
7. FAQ – XXY and XYY Syndrome

What is XXY Syndrome?

XXY syndrome, also known as Klinefelter syndrome, is a genetic disorder in males due to an extra copy of the X chromosome in each of their cells. Klinefelter syndrome occurs in about 1 in 600 people assigned male at birth (AMAB). XXY syndrome can be caused by a sperm cell carrying an extra X chromosome, an egg cell holding an extra X chromosome, and cells dividing incorrectly during early fetal development.

The symptoms of this condition may include a smaller penis, undescended testicles, atypical body proportions, a flat fleet, radioulnar synostosis, testicular failure, increased breast tissue, increased risk of blood clots, weaker bones or higher fractures, anxiety, depression, social, emotional or behavioural issues, impulsive behaviours, learning difficulties like reading and language challenges, attention deficit hyperactivity disorder, speech delays, and autism spectrum disorder.

XXY syndrome is diagnosed through physical examination, hormonal testing, and chromosomal testing. Furthermore, XXY syndrome can be treated through hormone replacement therapy, speech therapy, physical therapy, occupational therapy, emotional, behavioural, and family therapy, and surgery.

What is XYY Syndrome?

XYY syndrome is also known as Jacob syndrome. It is a genetic disorder in males due to an extra copy of the Y chromosome in each of their cells. XYY syndrome is caused by a random mix-up or mutation during the creation of a male’s genetic code. The symptoms of XYY syndrome may include hypotonia, delayed or difficulty in speech in babies, autism, attention difficulties, delayed motor skill development like writing, emotional or behavioural issues, hand trembling, hypotonia, learning disabilities, taller than average height, and infertility in teens.

XYY syndrome is diagnosed through physical examinations and chromosome analysis. Furthermore, treatment options for XYY syndrome may include speech therapy, physical or occupational therapy, and educational therapy.

Similarities Between XXY and XYY Syndrome

1. XXY and XYY syndrome are two aneuploidy disorders in males due to an extra copy of chromosome in the cells.
2. In both conditions, males have 47 chromosomes in each of their cells.
3. Both these can be diagnosed through physical examination and chromosome analysis.
4. They can be treated through specific therapies.

Difference Between XXY and XYY Syndrome

Definition

1. XXY syndrome is a genetic disorder in males due to an extra copy of the X chromosome in each of their cells.
2. XYY syndrome is a genetic disorder in males due to an extra copy of the Y chromosome in each of their cells.

Other Names

1. XXY Syndrome is also known as Klinefelter syndrome.
2. XYY Syndrome is also known as Jacob syndrome.

Causes

1. XXY Syndrome can be caused by a sperm cell carrying an extra X chromosome, an egg cell holding an extra X chromosome, or when cells divide incorrectly during early fetal development.
2. XYY Syndrome occurs due to a random mix-up or mutation during the creation of a male’s genetic code.

Symptoms

1. Symptoms of XXY Syndrome may include a smaller penis, undescended testicles, atypical body proportions, flat feet, radioulnar synostosis, testicular failure, increased breast tissue, increased risk of blood clots, weaker bones or higher risk of fractures, anxiety, depression, social, emotional, or behavioral issues, impulsive behaviors, learning difficulties such as reading and language challenges, attention deficit hyperactivity disorder, speech delays, and autism spectrum disorder.
2. Symptoms of XYY Syndrome may include hypotonia, delayed or difficult speech in babies and autism, attention difficulties, delayed motor skill development such as in writing, delayed or difficult speech, emotional or behavioral issues, hand trembling, hypotonia, learning disabilities, taller than average height, and potential infertility in teens.

Diagnosis

1. Diagnosis of XXY Syndrome may involve a physical examination, hormonal testing, and chromosomal testing.
2. Diagnosis of XYY Syndrome may include a physical examination and chromosome analysis.

Treatment

1. Treatment for XXY Syndrome may include hormone replacement therapy, speech therapy, physical therapy, occupational therapy, emotional, behavioral, and family therapy, and surgery.
2. Treatment for XYY Syndrome may include speech therapy, physical or occupational therapy, and educational therapy.

The following table summarizes the difference between XXY and XYY syndrome.

Summary – XY vs XYY Syndrome

XXY and XYY syndrome are two different aneuploidies in males. They are due to an extra copy of chromosomes in the cells, and in both these conditions, males have 47 chromosomes in each of their cells. However, XXY syndrome is due to an extra copy of the X chromosome in each of their cells, while XYY syndrome is due to an extra copy of the Y chromosome in each of their cells. This is the summary of the difference between XXY and XYY syndrome.

FAQ: XY and XYY Syndrome

1. What is the gender of XXY?

• XXY syndrome is typically seen in males. Therefore, the gender of XXY is AMAB (assigned males at birth). This disorder is a random error in cell division that happens when a parent’s reproductive cells are being formed.

2. Can XXY males get pregnant?

• Most XXY males are infertile. According to estimation, between 95% and 99% of XXY men are infertile because they do not produce enough sperm to fertilize an egg naturally. However, with advances in assistive reproductive technology (ART), it is possible for some men with XXY to conceive.

3. How does it test for XXY?

• The only way to confirm the presence of an extra chromosome is by karyotype testing. Therefore, the healthcare provider will take a small blood or skin sample and send it to a laboratory for chromosome analysis.

4. What are the effects of Jacob syndrome?

• Hypotonia, delayed or difficulty in speech in babies and autism, attention difficulties, delayed motor skill development like in writing, delayed or difficult speech, emotional or behavioural issues, hand trembling, learning disabilities, taller than average height, infertility in teens.

5. What is the IQ of someone with Jacobs syndrome?

• According to a recent systematic review, XYY boys and men have an average 99.5 verbal IQ and 106.4 performance IQ. Therefore, they may need educational assistance and therapy for a better life.

Reference:

1. “Klinefelter Syndrome.” Cleveland Clinic.
2. Holland, Kimberly. “XYY Syndrome: Causes, Symptoms, and More.” Healthline, Healthline Media.

Image Courtesy:

1. “Klinefelter’s syndrome” By Smithperiod6.Wikispaces (CC BY-SA 3.0) via Commons Wikimedia
2. “Amniocentesis results showing 47, XYY karyotype” By Dimitrios Athanatos, Christos Tsakalidis, George P Tampakoudis, Maria N Papastergiou, Fillipos Tzevelekis, George Pados, and Efstratios A Assimakopoulos – NCBI (CC BY 3.0) via Commons Wikimedia