Showing posts with label DNA. Show all posts
Showing posts with label DNA. Show all posts

Sep 18, 2015

Genetics vs. Genomics

The words genetic and genomic are often used interchangeably. However, they have different and specific meanings.

Genetics is the study of heredity. It is the study of how inherited traits are passed from one generation to the next through the genes, and how new traits appear by way of genetic mutations or changes. These traits may be characteristics like eye or hair color.

Genomics is a more recent term that describes the study of all of a person's genes (the genome). Genomics is defined as the study of genes and their functions, and related techniques.

The main difference between genomics and genetics is that genetics looks at the functioning and composition of a single gene and genomics addresses all genes and their inter relationships in order to identify their combined influence on the growth and development of an organism.

Genetic information is stored in the molecule DNA
Gene refers to a specific sequence of DNA on a single chromosome that encodes a particular product. Humans have many thousands of genes, spaced across the entire set of DNA.

The word genome encompasses the entire set of genetic information across all 23 chromosome pairs, including all genes, as well as gene-modifying sequences, and everything in-between.

In the context of clinical and research settings, "genetic" testing refers to the examination of specific bits of DNA that have a known function.

Genomic testing looks for variations within large segments across the entirety of genetic material, both within and outside known functional genes. It looks at groups of genes and how active they are, such as how a cancer is likely to grow and respond to treatment.

All the genes make up the genome. Both are important because understanding more about diseases caused by a single gene using genetics and complex diseases caused by multiple genes and environmental factors using genomics can lead to earlier diagnoses, interventions, and targeted treatments. 

Aug 28, 2015

Flash Drives Getting Smaller

The NAND (not and) flash technology that Toshiba introduced in 1989 (130nm or nanometers), making thumb drives, SSDs, (solid state drive) and smartphone memory, has finally reached a development dead end. Toshiba and other major manufacturers of 15 nm NAND flash are stopping new development and focusing development on 3D NAND.

For comparison, a strand of human DNA is 2.5 nm in diameter, and there are 25,400,000 nanometers in one inch. 1 centimeter = 10,000,000 nanometers.

Intel says it will be able to fit 1TB (terabytes) on a card just two millimeters thick in an object half the size of a postage stamp.

A square inch drive with a Terabyte of capacity can contain more bits than the Milky Way has stars (about 200 billion to 400 billion stars as estimated by astronomers). Obviously, when it comes to computers, size matters and smaller is better. Incidentally, My blog spoke of terabytes in 2010 LINK

Jun 19, 2015

Humans and Wallabies Share DNA

A tammar wallaby is a small- or mid-sized macropod found in Australia and New Guinea. They belong to the same taxonomic family as kangaroos. One of them, Mathilda, became the first kangaroo to have her genetic code mapped.

The Australian researchers were shocked when they compared her code with a human’s. They had expected the comparison to be a mismatch, but it turned out that the genomes of the two species were more than just similar. Apart from a few differences, the genes were identical, and many of them were arranged in the same order. Both species hold large pieces of genetic information about the other.

It made more sense when the researchers also discovered that people and these bouncy marsupials had a common ancestor that lived at least 150 million years ago. Mice separated from humans only 70 million years ago, but scientists feel that kangaroos can provide more answers about human evolution when it comes to why some DNA remained the same for eons while other DNA changed. By comparing different genomes from species, unknown genes can be identified, and Matilda revealed 14 new genes never before seen in kangaroos, which might possibly also be present in humans.

Mar 27, 2015


DNA is DeoxyriboNucleic Acid. The blueprint of every living thing on the planet is encoded in DNA. It can hold a lot of information. We could theoretically encode all the world's data (emails, movies, books, pictures, etc.) on just a few grams of DNA.

According to New Scientist, a gram of DNA could theoretically store 455 exabytes of data. The world has about 1.8 zettabytes of data, according to a 2011 estimate. All the world's information would fit on a four-gram DNA hard drive the size of a teaspoon. Also, given the right conditions, DNA can survive for thousands of years. Long past the time traditional hard drives have degraded.

Scientists at the Swiss Federal Institute of Technology in Zurich encapsulated DNA in tiny, dry glass spheres. The researchers say that DNA kept at a temperature of 10 °C would remain uncorrupted and readable for 2,000 years. At even lower temperatures the data could last two million years.

However, preserving data in DNA is currently very expensive. Swiss researchers spent $1,500 to encode 83-kilobytes, which is smaller than the size a picture taken on a smartphone uses. There are a nearly two quintillion kilobytes in the world's 1.8 zettabytes.

Sep 28, 2013


Did you know you can have your DNA analyzed for just $99? It used to cost $10,000. The web site has the information. Interesting information about diseases you may be inclined toward, based on your DNA. It also has Ancestry information, risk for some genetic diseases, cancer, and some possible drug responses you may have.

It takes a week to get the kit and a few seconds to swab your mouth, then 5 - 6 weeks to get results. I sent for my kit this week.

May 7, 2013

Gene Therapy Virus

In 2012 the European union authorized UniQure to use Glybera gene therapy for commercial use. The medicine sends a virus into your body, containing the correct genetic code. The therapy, developed by UniQure uses a virus to infect muscle cells with a working copy of the gene. Once the virus infects muscle cells, the correct code overwrites the bad DNA.

Glybera is used to treat lipoprotein lipase deficiency. One in a million people have damaged copies of a gene which is essential for breaking down fats. It means fat builds up in the blood leading to abdominal pain and life-threatening inflammation of the pancreas, pancreatitis.

A few years ago, three academic groups showed that AAV2, another adeno-associated virus, can correct a rare form of inherited blindness, by targeting a certain cell type within the retina.

Nov 30, 2012


Scientists announced that they have mapped the entire genome of the domestic pig, revealing that besides providing tasty bacon and sausages, the animal may also be useful in fighting human diseases.

The study published in the journal Nature found that pigs and humans share more than 100 DNA mutations that have previously been linked to diseases like obesity, diabetes, dyslexia, Parkinson's and Alzheimer's, according to US and European researchers.
"In total, we found 112 positions where the porcine protein has the same amino acid that is implicated in a disease in humans," researchers wrote.

Researchers said that because pigs share many of the same complex genetic diseases as humans, the animals would serve as excellent models for studying the underlying biology of human disease.

A domestic pig breed is already being used extensively in medical research because of its anatomical similarity to humans, and pig heart valves have been used by doctors to replace faulty human ones.

Scientists can use the new genome map to improve meat production by breeding a new generation of super-pigs that will grow faster, survive longer, produce more offspring and yield more meat for less feed.

"This new analysis helps us understand the genetic mechanisms that enable high-quality pork production, feed efficiency and resistance to disease," Sonny Ramaswany, director of the U.S. Department of Agriculture's National Institute of Food and Agriculture said, according to Reuters.

Scientists in the sequencing project compared the domestic pig's genome to that of the wild boar, human, mouse, dog, horse, and cow.

A recent study also revealed that pigs had the most olfactory receptor genes, which highlights the importance of smell in the scavenger animal's lifestyle, and that pigs also had fewer bitter taste receptors meaning that "pigs can eat food that is unpalatable to humans," which is one of the reasons why pigs have become such a highly valued farm animal. I am still trying to figure out how they will know if a pig has Alzheimer's.

Jul 8, 2011

Spit Your Age

Dr. Eric Vilain, a professor of human genetics, pediatrics and urology at the David Geffen School of Medicine at UCLA. "With just a saliva sample, we can accurately predict a person's age without knowing anything else about them." Vilain and his colleagues looked at a process called methylation – a chemical modification of one of the four building blocks that make up our DNA.

"While genes partly shape how our body ages, environmental influences also can change our DNA as we age," explained Vilain. "Methylation patterns shift as we grow older and contribute to aging-related disease."

Using saliva samples contributed by 34 pairs of identical male twins ages 21 to 55, UCLA researchers scoured the genomes and identified 88 sites on the DNA that strongly correlated methylation to age. They replicated their findings in a general population of 31 men and 29 women aged 18 to 70.

Next, the scientists built a predictive model using two of the three genes with the strongest age-related linkage to methylation. When they plugged in the data from the twins' and the other group's saliva samples, they were able to correctly predict a person's age within five years – an unprecedented level of accuracy. "Methylation's relationship with age is so strong that we can identify how old someone is by examining just two of the 3 billion building blocks that make up our genome," said first author Sven Bocklandt.

Mar 8, 2011

Reverse Aging

One cause of the physical degeneration associated with aging involves telomeres, which are segments of DNA found at the ends of chromosomes. Every time a cell divides, its telomeres get shorter, and once a cell runs out of telomeres, it can't reproduce anymore and dies. There is an enzyme called telomerase that reverses this process and it is one of the reasons cancer cells live so long.

In November, 2010, researchers at Harvard Medical School announced in Nature that they had administered telomerase to a group of mice suffering from age-related degeneration. The damage went away and the mice didn't just get better; they got younger. Proponents of the Singularity see this as just a natural progression and predict that aging is just another problem that can be overcome, likely in the next twenty to thirty years. I agree.