s disease is a common progressive thinking or understanding The disease primarily affects people over the age of 65 and the likelihood of developing Alzheimer s disease increases with age The disease is irreversible but there are medications available to help with the symptoms History In 1901 a German psychiatrist and neuroanatomist named Dr Alois Alzheimer met a 50 year old female patient named Auguste Auguste was admitted to a psychiatric hospital by her husband due to reports of severe paranoia sleep problems confusion and aggression Dr Alzheimer was intrigued by Auguste because he had never encountered a patient with her set of symptoms Dr Alzheimer decided to document her behavior and study her during her stay at the psychiatric hospital After admission into the hospital Auguste s symptoms rapidly worsened Due to this Auguste was admitted to permanent care at the hospital until her death in 1906 During her stay at the hospital Dr Alzheimer kept detailed notes on her symptoms and the progression of her disease After her death Dr Alzheimer was able to study Auguste s brain tissue It was during this autopsy that he found strange deposits around nerve cells At the time he could not explain his findings but he documented them in great detail Dr Alzheimer compiled his research and presented his findings to a team of physicians He presented both the physiological and histological reports he had kept on Auguste and told the physicians that this was an illness that had never been seen before Dr Alzheimer s work was officially published in 1907 and in 1909 Dr Alzheimer s work appeared in the famous textbook Psychiatrie A It was here in this textbook that the author suggested the disease be called Alzheimer s 19 20 21 TE 22 CITIDO HIGHE 16 X CHERE 17 XOCOL Figure 1 Karyotype of Trisomy 21 UMIE HA 18 A Surprising Connection During the years after Dr Alzheimer s work and as more documented cases of Alzheimer s disease appeared research became focused on finding the genes involved In the 1980s a team of scientists documented that people with Down syndrome suffer from early onset Alzheimer s disease at a disproportionately high rate in comparison to the general population nearly all individuals with Down syndrome will develop Alzheimer s by the age of 40 Since Down syndrome is classified as having an extra copy of chromosome 21 scientists hypothesized that the gene responsible for producing proteins associated with Alzheimer s must be located on this chromosome After performing analysis of the genes on chromosome 21 scientists found the Amyloid Precursor Protein APP gene This gene is highly concentrated in neurons the primary cell type of the nervous system Amyloid Precursor Protein Gene When De Alzheimer examined the brain tissue of Auguste he found strange build ups around the neurons Approximately eighty years after his findings scientists determined that these buildups were caused by excess proteins in the brain The APP gene provides instructions for making a protein called amyloid precursor protein This protein when produced property is important for the growth and repair of neurons The amyloid precursor protein is cut by enzymes to create smaller fragments peptides that are released from the cell and then used as needed If mutations occur at the APP gene however the sequence of amino acids is changed Specifically one amino acid valine is switched with isoleucine at position 717 This mutation causes the peptides to be longer and or or stickier than usual When these peptides are released from the cell they can accumulate and cause the buildups now known as plaques which Dr Alzheimer originally documented The two hallmarks of Alzheimer s disease are amyloid plaques and neuritic plaques Amyloid plaques are the result of a buildup of amyloid beta proteins and neuritic plaques are the result of a buildup of Tau proteins in the brain Bek Analysis Questions 20 Figure 2 The production of APP in a neuron APP is represented by the triangles 1 Using Figure 1 label the following neuron nucleus rough ER Golgi transport vesicles APP and exocytos 2 Using Figure 1 describe each step of the production and movement of the APP protein through a neuron