Trisomy 21 Definition and Characteristics

Definition and Causes

• Trisomy 21 is a genetic disorder caused by the presence of an extra copy of chromosome 21.
• It is the most common chromosomal anomaly, occurring in approximately 1 in every 700 births.
• The extra genetic material from the extra chromosome 21 leads to the characteristic physical and developmental features of the disorder.

Physical Characteristics

• Short stature and small head size
• Flat face with a small nose and eyes that are close together
• Small ears and hands
• Poor muscle tone
• Increased risk of congenital heart defects (40-50% of cases)

Developmental and Cognitive Features

• Delayed speech and language development
• Intellectual disability (range from mild to moderate)
• Delayed cognitive development
• Increased risk of attention deficit hyperactivity disorder (ADHD)

Health Complications

• Increased risk of infections (e.g. respiratory, ear, and skin)
• Increased risk of vision and hearing problems
• Increased risk of thyroid disorders
• Increased risk of leukemia and other cancers
• Respiratory problems (e.g. sleep apnea)

Diagnosis

• Prenatal diagnosis: chorionic villus sampling (CVS) or amniocentesis
• Postnatal diagnosis: physical examination and chromosomal analysis (karyotype)

Treatment and Management

• No cure for trisomy 21, but treatment focuses on managing the associated health problems
• Speech and language therapy
• Occupational therapy
• Physical therapy
• Medications for associated health problems (e.g. heart defects, thyroid disorders)
• Surgical interventions for congenital heart defects and other physical abnormalities

Definition and Causes

• Trisomy 21 is a genetic disorder caused by an extra copy of chromosome 21, occurring in approximately 1 in every 700 births.

Physical Characteristics

• Individuals with trisomy 21 typically have short stature and small head size.
• Facial features include a flat face, small nose, and eyes that are close together.
• Other physical characteristics include small ears and hands.
• They often have poor muscle tone and an increased risk of congenital heart defects (40-50% of cases).

Developmental and Cognitive Features

• Trisomy 21 is associated with delayed speech and language development.
• Intellectual disability is common, ranging from mild to moderate.
• Delayed cognitive development is also typical.
• There is an increased risk of attention deficit hyperactivity disorder (ADHD).

Health Complications

• Individuals with trisomy 21 are more prone to infections, such as respiratory, ear, and skin infections.
• Vision and hearing problems are also more common.
• There is an increased risk of thyroid disorders and leukemia, as well as other cancers.
• Respiratory problems, including sleep apnea, are common.

Diagnosis

• Prenatal diagnosis can be made through chorionic villus sampling (CVS) or amniocentesis.
• Postnatal diagnosis is made through physical examination and chromosomal analysis (karyotype).

Treatment and Management

• While there is no cure for trisomy 21, treatment focuses on managing associated health problems.
• Therapy programs include speech and language therapy, occupational therapy, and physical therapy.
• Medications may be prescribed to manage associated health problems, such as heart defects and thyroid disorders.
• Surgical interventions may be necessary to address congenital heart defects and other physical abnormalities.

Definition and Causes

• Trisomy 21 is a genetic disorder caused by an extra copy of chromosome 21.
• Occurs in approximately 1 in every 700 births.
• The extra genetic material leads to characteristic physical and developmental features.

Physical Characteristics

• Short stature and small head size.
• Flat face with a small nose and eyes that are close together.
• Small ears and hands.
• Poor muscle tone.
• Increased risk of congenital heart defects (40-50% of cases).

Developmental and Cognitive Features

• Delayed speech and language development.
• Intellectual disability (range from mild to moderate).
• Delayed cognitive development.
• Increased risk of attention deficit hyperactivity disorder (ADHD).

Health Complications

• Increased risk of infections (respiratory, ear, and skin).
• Increased risk of vision and hearing problems.
• Increased risk of thyroid disorders.
• Increased risk of leukemia and other cancers.
• Respiratory problems (e.g. sleep apnea).

Diagnosis

• Prenatal diagnosis: chorionic villus sampling (CVS) or amniocentesis.
• Postnatal diagnosis: physical examination and chromosomal analysis (karyotype).

Treatment and Management

• No cure for trisomy 21, but treatment focuses on managing associated health problems.
• Speech and language therapy.
• Occupational therapy.
• Physical therapy.
• Medications for associated health problems (e.g. heart defects, thyroid disorders).
• Surgical interventions for congenital heart defects and other physical abnormalities.