THE DETECTION OF ALBINISM

 THE DETECTION OF ALBINISM 

               

    Albinism is a medical condition that affects a person's skin color, eye color, and hair color; it tends to be white. This condition is cause by the decrease of tyrosinase activity. Albinism has different types of patterns, it depends on the genes of the chromosomes and the mutation that occurs. It is an inherited condition, that is considered to be an autosomal recessive defect. This means that it is passed on from family members; meaning there must be a history of this condition in the family. According to one of the websites, "In certain ethnic groups we found at least one mutation in all, and two mutations in over 90% of albinos."  

    This medical condition can be detected by a "..light and electron microscopic examination of melanogenesis in fetal scalp biopsies or by molecular genetic tests" during pregnancy. The physical appearance of the individual can involve a major factor for detection; their skin pigmentation, eye color, and hair color is white and abnormal. This condition can also be associated with bowel disease and bleeding problems. When an individual suffers from this condition it is important for the individual to speak with their doctor to explain the treatment and restrictions; such as avoiding a long time in the sun, and wearing sunscreen. 

 

1. Prenatal diagnosis and carrier detection of albinism | Genetics in Medicine (nature.com)

2. Albinism | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program (nih.gov)

New cause for Progressive Myoclonus Epilepsies (PME) has been identified.

     One of the most devastating forms of epilepsy is progressive myoclonus epilepsy. An team of researchers have discovered a new gene that causes this type of epilepsy. It was shown that a single mutation in a potassium ion channel is the main reason for this disease. Researches at University of Helsinki, Finland and Universities of Melbourne and South Australia have identified a new gene for a progressive form of epilepsy. 

     Progressive myoclonus epilepsies (PME) are rare and inherited. They are usually childhood-onset neurodegenerative diseases. The goal of the study was to identify underlying genetic causes in 84 PME patients. They did so using DNA sequencing targeting the protein coding elements of the human genome. A genetic diagnosis was found for 1/3 of the unsolved patients. The most successful finding from the study was that a single mutation in a potassium channel encoding gene (KCNC1) is the cause for a large number of unsolved PME patients. They found that there was a mutation was found in 13 patients that were not inherited from parents, as usual. It had emerged in a germ cell of one of the parents or in the fertilized egg. It was found that each of the 13 patient had dozens of these new mutations, however, they are rarely disease causing. The researchers estimate that this mutation occurs in roughly 1 out of every 5.7 million, being very rare. However, with such a large population on earth, t at least hundreds of people could have this mutation globally.

     "A fascinating aspect of this finding is that this single mutation can be found in several patients all over the world. The mutation site is an example of a 'mutation hotspot' of the genome - a DNA nucleotide which is more prone for alterations", says Professor Anna-Elina Lehesjoki, the corresponding principal investigator of the study in University of Helsinki and Folkhälsan Research Center, Finland. "The fact that the mutation occurs in a well-characterized ion channel gives hope to development of targeted therapy. There are anti-epileptic drugs in the market that target other similar ion channels and follow-up research aims to discover a way to rescue the function of the channel in PME patients."

     The mutation disrupts the function in a potassium channel, which has a central role in signal transmission in the brain. The mutation causes in inhibitory signals in certain parts of the brain to be reduced, which makes patients more susceptible to epileptic seizures and myoclonus in early childhood stages. The mutation also causes degeneration of the cerebellum and subtle cognitive decline.

     I think these findings really bring epileptic studies a long way. The knowledge they now have could potentially aid in diagnostics and potential therapeutic medications for the disease. The study also proved how significant DNA technologies are and how powerful they are in understanding the underlying genetic causes of severe diseases.

Article: http://www.medicalnewstoday.com/releases/285642.php

Inherited Alzheimer's Damage Greater Decades Before Symptoms Appear

A study investigating an inherited form of Alzheimer's disease shows the progression of the disease may slow once symptoms appear and do significant damage. Professor Colin Masters, from the Florey Institutie of Neuroscience and Mental Health and University of Melbourne, found rapid neuronal damage beginning 10-20 years before symptoms appear. Professor Master stated, "There is actually a slowing of the neurodegeneration." Families with autosomal dominant Alzheimer's are vital because years before symptoms arise, they can be diagnosed. Information gathered will also help treatment for those with age-related Alzheimer's disease. 1% of Alzheimer's patients have the genetic type of the disease. The next step of the study is the clinical trail. They will monitor the subjects with MRIs, PETs, blood tests, and cerebrospinal fluid.
The fact that only 1% of all Alzheimer's patients are the genetic form is shocking. That is good news, though, because it means a person does not pass it on to their progeny. Improving the treatment is very important for both the genetic and non-genetic types of the disease.

Molecular Defense against Huntington Disease

Leicester geneticists have discovered a potential defence against Huntington's disease a fatal neurodegenerative disorder which currently has no cure. A team of experts from the University's Department of Genetics carried out research for more than six years to identify new potential drug targets for the disease.


The team of University of Leicester researchers identified that glutathione peroxidase activity a key antioxidant in cells protects against symptoms of the disease in model organisms.
They hope that the enzyme activity whose protective ability was initially observed in model organisms such as yeast can be further developed and eventually used to treat people with the genetically-inherited disease. The disease affects around 12 people per 100,000.

http://www.sciencedaily.com/releases/2013/08/130825171552.htm
http://mindletters.com/2012/10/10/dear-dr-huntingtons-disease/

Left Handedness is not " in the genes"

It is said that over 10 % of Americans are left handed an the same goes for other countries. Some researches say they are not exactly sure what causes people to be left or right handed , but Professor Armur form University of Nottingham and Dr. Davison of  University College of London are suggesting that left handedness does not come from genes therefore isn't inherited. This study used 2,000 set of twins from London Twin Research Unit. In this study researchers compared left and right handedness and looked at over 4,000 people and their genome and found no link to handedness and genes. There research in this article has challenged a previous study that said handedness was linked to a gene called PCSK6. Professor Armur and Dr. Davison believe that there should be a noticeable difference between right and left do to differences in genetic variation. At the end of their study they have determined that handedness is a mixture or a combination of genes, environment, and cultural pressure to conform.

I choose this article because I thought it was interesting and for the fact that the question of handedness was still left some what unanswered because even though the article ends with some ideas about what causes handedness I get the feeling that researchers still are not exactly sure on what the true causes for handedness are. I also found it interesting for the article to included that it could be pressure from  people to conform to society that makes people be left or right handed. I have heard of people forcing or teaching their children to be right handed so I found it easy to correlate the information form this article to real life.  

  

http://www.medicalnewstoday.com/articles/267047.php