About Down Syndrome

Down syndrome is a genetic condition caused by the presence of a full or partial extra copy of chromosome 21. This additional genetic material affects physical and cognitive development and leads to the common characteristics associated with the condition.

Individuals with Down syndrome may experience developmental delays, intellectual disabilities, distinctive facial features, and various physical and medical complications. While there is no cure for Down syndrome, medical care, therapy, educational support, and early intervention services may help improve quality of life and daily functioning.

Children and adults with Down syndrome may also experience additional health conditions involving the heart, respiratory system, digestive system, hearing, or vision.

Causes of Down Syndrome

Down syndrome occurs when abnormal cell division results in extra genetic material from chromosome 21.

There is no known action or behavior that directly causes Down syndrome. In many cases, parents of children with Down syndrome do not have any genetic abnormalities themselves.

Some medical professionals believe that advanced maternal age may increase the likelihood of having a child with Down syndrome.

Types of Down Syndrome

There are three primary types of Down syndrome, each involving different amounts or arrangements of chromosome 21.

Standard Trisomy 21 (Non-Mosaic Down Syndrome)

This is the most common form of Down syndrome and occurs when every cell in the body contains an extra copy of chromosome 21.

Approximately 90% to 95% of individuals with Down syndrome have Standard Trisomy 21.

Mosaic Down Syndrome

Mosaic Down syndrome occurs when only some cells contain an extra copy of chromosome 21.

Individuals with Mosaic Down syndrome may experience fewer or milder symptoms compared to those with Standard Trisomy 21.

This form is relatively rare and accounts for about 1% of Down syndrome cases.

Translocation Down Syndrome

Translocation Down syndrome occurs when an extra part of chromosome 21 becomes attached to another chromosome.

Symptoms of Down Syndrome

Symptoms and severity can vary widely from person to person. Some individuals may experience mild limitations, while others may have significant physical or intellectual impairments.

Common Facial Characteristics

Individuals with Down syndrome may have:

• Slanted eyes

• Flattened nose

• Small ears

• Misshaped mouth or tongue

• Crooked teeth

Common Physical Characteristics

Physical characteristics may include:

• Short stature

• Short neck

• Short arms and legs

• Low muscle tone (hypotonia)

Common Health Issues Associated with Down Syndrome

Individuals with Down syndrome may also experience:

• Heart defects

• Respiratory problems

• Vision problems

• Hearing loss or hearing problems

• Dental complications

• Intellectual disabilities

• Depression

• Hypothyroidism

Qualifying for Social Security Disability with Down Syndrome

The Social Security Administration (SSA) evaluates Down syndrome claims using the Blue Book.

Individuals with Standard Trisomy 21 (non-mosaic Down syndrome) are generally evaluated under Listing 10.06 – Non-Mosaic Down Syndrome.

Individuals with Mosaic Down syndrome or Translocation Down syndrome may instead be evaluated under listings related to the body systems affected by their symptoms, such as hearing, vision, or intellectual functioning.

Listing 10.06 – Non-Mosaic Down Syndrome

An applicant may qualify for disability benefits if they meet one of the following requirements.

Requirement A

A laboratory report showing karyotype analysis confirming Down syndrome, signed by a physician or accompanied by a physician’s statement.

Requirement B

A physician’s report stating that the applicant has Standard Trisomy 21 or chromosome 21 translocation consistent with prior karyotype analysis, along with distinctive physical characteristics of Down syndrome.

Requirement C

A physician’s report confirming Down syndrome with distinctive physical characteristics and evidence showing functional limitations consistent with non-mosaic Down syndrome.

Medical-Vocational Allowance

If an applicant does not meet the exact requirements of a Blue Book listing, they may still qualify for disability benefits through a medical-vocational allowance.

Under this evaluation, the SSA considers whether the condition prevents the individual from performing unskilled work.

Unskilled work generally refers to jobs requiring little training or education.

The SSA evaluates factors such as:

• Intellectual functioning

• Communication abilities

• Physical limitations

• Ability to complete tasks independently

• Social functioning

• Work-related limitations

If Down syndrome symptoms significantly interfere with a person’s ability to maintain consistent employment or perform basic work activities, disability benefits may still be approved.