Aurora magazine

University of Missouri researchers have identified a specific mutation in the gene that causes Chédiak-Higashi syndrome. The disease causes the immune system to weaken, making the body much more vulnerable to infections. Professor Leslie Lyons and Dr. Reuben Buckley have found a possible answer in a cat's DNA.

Doctors already knew the gene responsible for the syndrome. The problem was that different treatments affect different parts of the gene, changing the final effect. Without knowing the exact mutation responsible for a specific disease, it is therefore impossible to develop a truly effective treatment. To solve this, the team of researchers used genetic sequencing techniques.

Professor Lyons worked with the late Smokey, a 16-year-old cat with Chédiak-Higashi syndrome. Thanks to in vitro fertilization, the teacher used the cat's semen to create a model of the disease. Starting from this, she and her team analyzed the genetic characteristics of this and other genetic diseases.

The team's discovery will have repercussions on human medicine and also on veterinary medicine. Knowing how the "guilty" gene works helps to better understand the syndrome in humans, albeit with all the necessary distinctions. Thanks to further studies, it will be easier to develop life-saving therapy for those suffering from this genetic disease. In addition, the discovery will improve the genetic tests that are used in breeds of purebred dogs and cats.

Source: missouri.edu

Chédiak-Higashi syndrome is a rare genetic disorder that affects the immune system. The disease causes a defect in the phagocytic cells, which fail to process and eliminate bacteria. This causes the appearance of giant lysosomal granules in neutrophils, neural cells and others. All this would be caused by an anomaly in the LYST (lysosomal trafficking regulator) gene.

The accumulation of granules causes a wide range of symptoms in patients. The most evident ones are albinism and the tendency to get sick much more often than average, especially due to respiratory infections. In addition, about 80% of patients experience an accelerated phase of the disease. During this time, the patient suffers from fever, jaundice, increased liver and spleen volume, enlarged lymph nodes. Typically, all of this leads to death in about 30 months.

Diagnosis occurs by analyzing a peripheral blood sample, looking for granules. A bone marrow sample is also examined to check the status of the cellular precursors of leukocytes. Genetic tests are used to confirm the diagnosis given by clinical observations. Usually, it is not necessary to examine close relatives, except in suspicious cases.

To date, the only effective therapy is hematopoietic stem cell transplantation. In these cases, approximately 60% of patients survive five years after transplantation. Without a compatible transplant donor, the prognosis is much more negative: most patients die within 7 years of age. Antibiotics can help prevent infections, but they are not a remedial therapy.

Source: msdmanuals.com

A study by the Genetics and Molecular Medicine department of King's College London provides new data on acne. This problem, so widespread among adolescents, often linked also to hormonal dysfunctions, has a genetic basis. In fact, the researchers identified the genes that influence their progress.

Acne is a disorder caused by inflammation of the sebaceous glands, which causes blackheads and small pustules. In severe cases, inflammation touches the deepest layers of the skin, causing cysts and nodules. If not treated properly, both superficial and deep acne can cause psychological discomfort and leave permanent scars.

In women, the disorder can be caused by hormonal disorders such as the polycystic ovary. However, this does not explain all the cases nor the different trends of the disease. For this reason, the British team involved around 27,000 volunteers, including 5,600 affected by severe acne. The researchers analyzed the DNA of all the volunteers, looking for genetic variants related to the development of acne.

Genetic analyzes have shown anomalies common to those suffering from severe acne. The variants are concentrated in the genes that influence the shape of the hair follicles. Depending on how the follicle is made, this can in fact contain more or less bacteria from the Propionibacterium acnes family. The richer the bacterial colonies, the more severe and difficult to eradicate acne.

The discovery will help develop better treatments than current ones. The therapies available today consist almost all of antibiotic creams and oral antibiotics.

Source: humanitasalute.it

Dr Ruth Mace of University College London has published a study on factors influencing menopause. According to the study, conducted on over 3,000 women, having multiple sexual intercourse could delay the phenomenon. The absence of relationships would in fact mark the end of the reproductive period for the organism.

The end of the fertile period brings with it a series of negative consequences for the organism, which go far beyond the impossibility of conceiving. Hormonal changes cause psychological and physical discomforts, including an increased risk of osteoporosis and cardiovascular disease. For this reason, the author of the study studied how to delay it as much as possible. From what emerged, sexual activity could help move the phenomenon forward.

The research team analyzed data from 3,000 women around 45 years old, collected during a study conducted between 1996 and 1997. At that time, none of the women were in menopause. The researchers also interviewed women about their health, eating habits, frequency of sexual intercourse and masturbation. About 50% of respondents said they had sex once a week. Ten years later, researchers returned to interview them.

In 2007, 1 in 2 women entered menopause around the age of 52. The theme of Dr. Mace has crossed the data with those collected in 1997, revealing a correlation between the age of menopause and sexual habits. In women with an active intimate life, the odds of entering menopause early were 28% lower. However, the reasons for the phenomenon are unclear.

According to study co-author Megan Arnot, early menopause may be an adaptive response. The absence of intercourse would be the signal that the woman is no longer seeking pregnancy, which would push the body to stop ovulating. At the moment, however, they are only conjectures.

Source: lastampa.it