Genetic/Chromosomal Disorder Presentation By: Brian Smith

Tay Sachs

How It Occurs Tay Sachs occurs when a person has an abnormal level of a fatty substance called ganglioside GM2. Ganglioside GM2 will accumulate in the nerve cells of the brain due to the absence or low level of an enzyme called hexosaminidase A (Hex-A)

History Tay Sachs is named after two separate individuals. Warren Tay ( ) who was a British ophthalmologist who in 1881 found and described a cherry red spot on the retina of one of his patient’s eye. Bernard Sachs ( ) was a New York neurologist who several years after Tay provided the first description of the cellular changes that attribute to the Tay Sachs disease.

Genetics of Tay Sachs Tay Sachs is a disease that can only be passed from one generation to the next. An individual will get Tay Sachs if they receive the faulty recessive gene for Tay Sachs from both parents. Most people could have the gene for Tay Sachs and not actually have Tay Sachs.

Type of Mutation Tay Sachs is a genetic mutation of the 15 th Chromosome. Tay Sachs occurs when a certain loci on the 15 th chromosome that codes for the enzyme Hex-A is faulty and the enzyme isn’t produced properly or not at all.

Phenotypic Effects The child will look and seem perfectly normally when born. Around 6 months, the child may start to lose certain normal functions and begins to act abnormal. The child will experience a long list of things: loss of peripheral vision, recurrent seizures and diminishing mental functions.

Diagnosis There is no way to diagnosis Tay Sachs before it occurs. To diagnosis Tay Sachs, a full physical examination will be taken as well as family history regarding the Tay Sachs disease. Finally the doctor can check the retina of the eye to see if there is the common “cherry- red” spot.

Diagnosis cont. Blood Tests can be taken to measure the Hex- A activity in the body. Biological Parents can also be tested to see if they both contain the gene for Tay Sachs. There is no cure or treatment.

Treatment There is no cure or treatment. The patient will die by the age of 5.

Bibliography "Tay-Sachs Disease: symptoms, treatment, cause, prevention, risks, complications, statistics, long-term outlook." MamasHealth.com: simple, easy to understand information about health. Web. 04 Nov "Tay-Sachs Disease - Diagnosis and Treatment Options at Mayo Clinic." Mayo Clinic: Medical Treatment and Research Centers. Web. 04 Nov