The human genome is a complete set of instructions for human beings. It is made up of 23 pairs of chromosomes and each pair has between 500 – 5,000 genes. Genes are responsible for particular traits such as eye color, hair color, etc. All pairs of chromosomes are the same in a man and a woman except one, the sex chromosome. Men have a Y and X chromosomes (XY) while women have two X chromosomes (XX).
Some changes to genes and chromosomes cause abnormal production of sperm or blockage to flow of sperm that leads to male infertility.
Chromosomal conditions are the most common genetic causes of male infertility. Chromosomal conditions that affect sperm production include Y chromosome deletions, Klinefelter’s syndrome, prader-willi syndrome, and other genetic conditions such as Down syndrome.
Infertility due to a gene mutation is less common. Mutations in the cystic fibrosis gene result in the congenital absence of the vas deferens. This causes blockage to flow of sperm. Other genes linked to fertility are those that prevent the testicles from descending.
It is likely that other genetic conditions will be found in future that will allow scientist to explain other causes of male infertility that currently have no known cause.
Why do people undergo cosmetic surgery? It’s a simple question that’s unlikely to yield a simple answer.
Cosmetic surgery’s original intention was to treat the patients who have injured their physical appearances such as physiognomy. However, including Korea, lots of countries’ denizens are undergoing cosmetic surgery in order to achieve “beauty”.
A common comment from those who have gone under the knife or needle is “I do it for myself.” But what does that really mean? Maybe that the patient decided on surgery because of the benefits it confers on the self, not for any effects it might have on others, such as romantic partners or rivals. “I do it for myself” also emphasizes the free will of the patient: he or she doesn’t feel pressured into surgery by outside forces, such as peer pressure, the media, or advertisements.
However, new research published recently has questioned the motives of those who opt for cosmetic procedures and suggests that they may be more complex than many would care to admit.
One of the clearest benefits of cosmetic surgery is that it improves appearance. If it didn’t, nobody would spend the money or go through the pain associated with those procedures.
Most of us would rather be more attractive than our peers because attractiveness confers all kinds of benefits, including the ability to compete for higher-value partners.
According to researchers, hundreds of genetic mutations start to form in embryo cells soon after conception. The researchers from Yale University and Mayo Clinic said that numerous of these mutations take place as sex cells form in the embryo. That means they became part of the genome of the embryo and can be passed on to the next generation.
The study author Flora Vaccarino said that their research opens up a new perspective on human development. The research findings show that some of the human genomes do not come from the parents.
According to the researchers, these early genetic mutations are like those found in cancer. This suggests that sometimes cancer occurs as a normal by-product of cell division.
The scientist added that their findings provide new insight into causes of disease such as autism and schizophrenia. These disorders are primarily the outcome of genetic abnormalities, but no genes inherited from parents have been found to cause such cases.
In addition, the study may help to explain why one identical twin may be healthy while the other has a genetic disorder, or why some family members who carry disease-causing mutations do not get sick.
Even though people share some characteristics with their family members and their peers, every person has an exceptional combination of traits. Some traits are acquired through learning while others are controlled by genes that children inherit from their parents. The following are some examples of traits that are easily observed.
Attachment of earlobe is a continuous trait. However, most earlobes can be classified as attached or unattached, or in-between. Some sources say that earlobe attachment is controlled by a single gene, and unattached earlobes are dominant over attached earlobes.
Some people can roll their tongue while others cannot. About 70 percent of people of European ancestry can roll their tongues, according to 1940 study by Alfred Sturtevant. Although many sources state that rolling of the tongue is controlled by a single gene, Sturtevant observed that people can learn to twist their tongue as they get older.
A dimple is a small natural indentation on the chin or in the cheek. Dimples can appear on both or one side. Some individuals are born with dimples while others develop them later in childhood. Dimples are heritable and individuals who have dimples tend to pass them to their children.
Epidermolysis bullosa is a genetic disease that causes blisters and chronic wounds. Epidermolysis bullosa occurs when the epidermal layer of the skin cannot attach fitly to the underlying dermis by the mutated connective protein. Epidermolysis bullosa is known as an incurable disease. Treatment only cares for blisters and prevent a new one. However, there is a good news. A few days ago, a team announced that a seven-year-old Syrian boy who transplanted transgenic replacement because of epidermolysis bullosa showed some progress. In 2015, regenerative medicine specialist Michele De Luca met doctors in Germany whose Syrian patient was suffering by epidermolysis bullosa. Laminin b3, a protein that regulates the attaching epidermal cells, was not encoded properly in the patient’s gene. Although Syrian boy met a doctor in Germany, his condition became more severe. He even lost approximately 80 percent of his epidermis. De Luca had experience in transgenic cell therapy. His patients were lack of small patches of the epidermis. On the other hand, the boy needed approximately 80 percent of replacement. However, his condition was the worst and his parents decided to treat their son using transgenic cell therapy. From his biopsy, keratinocyte, a bountiful cell type in the epidermis, was extracted and transducted so that the gene in the boy’s cell encodes the laminin b3. After the cells grow enough to cover his epidermis, they were grafted in two operations. After the operations, his new skin attached properly to the underlying dermis and had appropriate levels of laminin b3. Now, his skin does not show any defects. According to Michele De Luca, “he’s back to school, he’s exercising, he’s started to play soccer… it’s quite amazing.”
Other scientists showed a positive response.
“It establishes a landmark in the field of stem cell therapy,” Elaine Fuchs, a skin scientist at the Rockefeller University.
“The work provides in-depth, novel information on skin stem cells and demonstrated the great potential of these cells for treating a devastating disorder,” says Allessandro Aiuti, a professor at the San Raffaele Scientific Institute
Myriads of people, who were eager to stop aging, were desperate to find any solutions to stop the process. Aging is a natural phenomenon or a process that is certainly unavoidable. However, people have firm belief that they can do certain things in order to delay aging process on their skins.
Unfortunately, however, researchers in the University of Arizona just proved that those efforts are futile because it is mathematically impossible to half aging in multicellular organisms like humans.
When aging is happening, two things are getting processed in our body. One, the cells slow down and start to lose function. For example, hair cells stop making hair pigments and make the hair to turn white. The other thing is that some cells crank up their growth rate, which can cause cancer cells to form. This means that when we are old, we have some cancer cells in our body. Even if it doesn’t show as a symptom, we still own those cancer cells. Even the researchers give an example: “even if natural selection were perfect, aging would still occur, since cancer cells tend to cheat when cells compete.”
Overall, although human mortality is an undisputed fact of life, the researcher’s explanation easily and clearly demonstrates the fact that it is inevitable to avoid death or aging.
Researchers from Italy, South Africa, and Canada identified a new gene that can lead to sudden death among athletes and young people early this year. The gene, known as CDH2, develops arrhythmogenic right ventricle cardiomyopathy (ARVC, a genetic condition that predisposes people to cardiac arrest. As a result, the gene causes unexpected death in healthy young people.
Published in Circulation: Cardiovascular Genetics, the discovery is the result of a collaboration that started 15 years ago. The study was led by a team in South Africa headed by Bongani Mayosi, a professor at the University of Cape Town, along with scientists of the University of Pavia and the Italian Auxologico Institute of Mila. A team of researchers from Hamilton Health Sciences and the Population Health Research Institute of McMaster University, led by Dr. Guillaume Paré, carried out the bioinformatics analysis, as well as the genetic sequencing for the study.
According to Paré, the discovery is important news for friends and family who have had a young person suffer a sudden cardiac death. They can now know that mutation in CDH2 is the culprit in a percentage of these patients.