Scientists create human sperm


Newcastle: British scientists created human sperm from stem cells for the first time in a bid to better understand the causes of male infertility.

The researchers, led by Karim Nayernia from Newcastle University, developed a technique to turn stem cells with male chromosomes from human embryos into reproductive cells, known as germline, and prompt them to divide, they said in a study published in the journal Stem Cells and Development today. The divided cells produced functional sperm, the scientists said.

The new technique “will allow researchers to study in detail how sperm forms and lead to a better understanding of infertility in men,” Professor Nayernia said in a statement released with the study. “This understanding could help us develop new ways to help couples suffering infertility so they can have a child which is genetically their own.”

The research may also help scientists understand how genetic diseases are passed on, according to the statement.

The lab-created sperm won’t be used for “fertilization of human eggs and implantation of embryos,” the researchers said. “While we can understand that some people may have concerns, this does not mean that humans can be produced ‘in a dish’ and we have no intention of doing this,” they wrote.

Stem cells, which have the power to become any type of cell in the body, are controversial when research involves human embryos, which are killed when the cells are harvested.

In another medical journal last week, more than 40 scientists, bio-ethicists, lawyers and science journal editors called on their colleagues and policy makers to develop guidelines for the research and reproductive use of stem cell- derived eggs and sperm.

Eggs the new superfood

London: Eggs blamed for raising levels of bad fats in the blood are now being labelled a “superfood” following new research.

According to a new report published in the British Nutrition Foundation’s Bulletin they have no “significant impact” on heart disease or cholesterol levels and could actually protect against these health problems.

Dr Bruce Griffin of the University of Surrey’s school of biomedical and molecular science analysed 30 egg studies, among them one from Harvard University which showed people who consumed one or more eggs a day were at no more risk of suffering from cardiovascular disease than non-egg eaters.

Egg yolks contain cholesterol, but nutritionists now know it is the saturated fats in food, not dietary cholesterol, that raises blood cholesterol levels, a risk factor for heart attacks.

Dr Griffin said that it was erroneous to view eggs soley in terms of their dietary cholesterol content and to ignore the potential benefits.

The British Nutrition Foundation says that one egg provides 13 essential nutrients, all in the yolk (egg whites contain albumen, an important source of protein, and no fat). They are also an excellent source of B vitamins, which are needed for vital functions in the body, and also provide good quantities of vitamin A, essential for normal growth and development.

An egg’s vitamin E content protects against heart disease and some cancers; there’s also vitamin D, which promotes mineral absorption and good bone health. Eggs are rich in iodine, for making thyroid hormones, and phosphorus, essential for healthy bones and teeth.

Teenage girls who eat an egg a day may give themselves additional protection against breast cancer in later life, according to a study in the journal Breast Cancer Research. It is the essential nutrients in eggs, such as amino acids, vitamins and minerals, that may be responsible for this protection.

Egg yolks contain the nutrients lutein and zeaxanthin, which could help to prevent or even reverse the age-related eye problem macular degeneration (MD). This is one of the leading causes of blindness and occurs as a consequence of getting older — however, low lutein intake is implicated as a risk factor.

Eggs are also low in calories — a large egg contains only 75 calories and 5 grams of fat — and other research suggests they can help you lose weight.

A study published last year in the Journal of the American College of Nutrition looked at the breakfast habits of obese women. Scientists from the Wayne State University in Detroit found that when the women were given either an egg or bagel breakfast, each providing the same number of calories, the women eating the eggs felt fuller and consumed fewer calories overall in the following 24 hours.

Health experts used to recommend a maximum egg consumption of three a week to avoid a rise in blood cholesterol levels. But since evidence has shown that it is saturated fat intake that affects cholesterol, advice has changed.

According to the British Egg Information Service, storing eggs correctly is vital to maintaining their freshness and nutrient content. They advise buying eggs only from a reputable retailer, keeping them in the fridge in their box and eating by the use-by date.



This contains the 25 amino acids which are the building blocks of the body and is found in fish, meat, beans, peas, lentils, eggs, cheese and soya.