Genetic Disorders

A chromosome is a thread-like molecule that carries hereditary information, from everything from height to eye colour. There are 23 pairs of chromosomes in every human cell and each one consists of a protein and a DNA strand. DNA is the genetic instruction for life and acts as a set of blueprints for the cell.

A genetic disorder is caused by an abnormality of an individual's DNA.

Down Syndrome

Down syndrome is the most common genetic disorder caused by a chromosomal abnormality. It arises from a defect involving chromosome 21, which results in mild to moderate developmental disabilities. Down syndrome affects approximately 1 in every 600 births, here in South Africa.

There are three types:

1. Non-disjunction Down syndrome (Trisomy 21) is when there is an extra chromosome 21 in every cell. It is the most common type, resulting in about 95% of all Down syndrome cases.

2. Mosaic Down syndrome is when there is an extra chromosome 21 in some, but not all, of the cells. The rest of the cells have the standard chromosome 21 pairing.

3. Translocation Down syndrome is when part of chromosome 21 breaks off and attaches (translocates) onto another chromosome. This is the only type of Down syndrome that can possibly be hereditary.

Congenital Heart Defect

A congenital heart defect is a defect in the structure of the heart and great vessels that is present at birth. This affects more than half of the babies born with Down syndrome.

If a baby has Down syndrome, its heart will be carefully assessed by a cardiologist after birth. Surgery may be needed if there are any defects threatening the health and well-being of the child.

Tax and Disability

Up until the 2014 year of assessment, taxpayers were entitled to a tax deduction for qualifying medical expenses, from their taxable income. From 2015, a medical tax credit is applicable, which acts as a rebate. This reduces your tax payable, as opposed to your taxable income.

A taxpayer who has a spouse or child with a disability (or who himself is disabled), can benefit from greater tax relief when calculating their medical tax credit.

A disability is defined as:

• a moderate to severe limitation of a person's ability to function or perform daily activities,
• as a result of a physical, sensory, communication, intellectual or mental impairment.
• The limitation must have lasted or has a prognosis of lasting more than a year.
• and must have been diagnosed by a duly registered medical practitioner.

An ITR-DD form (confirmation of diagnosis of disability form for an individual taxpayer) must be completed by the taxpayer and a qualified medical practitioner.

A physical impairment is not a "disability" as defined, as it is:

less than a moderate to severe limitation of a person's ability to function or perform daily activities,
• after maximum correction (i.e. appropriate therapy, medication & use of devices)

Certain expenses qualify if they are as a result of a physical impairment and are required or needed, as well as paid by the taxpayer, during the year of assessment. There will however be limitations, as it is not a disability.


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