Couples planning a baby will be able to take a saliva test to see if either of them carry recessive genes that could lead to their child having cystic fibrosis, spinal muscular atrophy or sickle cell anaemia, reports the Telegraph. People with a

, the condition can lead to convulsions, kidney failure and serious liver problems."If this is a gene responsible for pre-eclampsia in some families then it would be a nice genetic test," said study leader Dr Raghu Kalluri. The team are now planning a large

In gene therapy, a healthy copy of a faulty gene is put into the body to correct the defect and Dr Simon Waddington, from University College London, said his team had been investigating how such therapies could be delivered in the womb. Researchers

gene called SRY that determines maleness by triggering the development of testes and making male hormones.Professor Graves mentioned two species – a rat in Japan and a type of mole vole - that don’t have a Y chromosome or SRY gene, but that are still

is constantly evolving but the exact causes are as yet still unknown."The difficulty of establishing gene involvement is compounded by the interaction of genes with the environment. Genetic testing for autism is still a long way off, given that autism is so

preimplantation diagnosis (PGD).Many women who test positive for the gene have their breasts surgically removed to avoid the disease.Only one other woman – an Israeli mother-to-be – is thought to have become pregnant after undergoing the embryo screening

fertility.The test follows the discovery of a gene called Fragile X, which indicates the rate at which a woman's egg supply diminishes over time. Women are born with a limited amount of immature eggs, only a small proportion of which turn into mature eggs. A

Men with the highest IQ also have the healthiest sperm, according to an evolutionary psychologist, reports the Telegraph. The qualities of being smart and funny may have evolved to become signals to women looking for a partner with healthy genes

Boys are genetically programmed to play with cars and balls rather than dolls, say American scientists.The tests, involving 30 children - 17 boys and 13 girls - suggest biological differences dictate the toys children enjoy playing with rather than

A team from the Institute of Psychiatry analysed data from 425 former US soldiers who served during the Vietnam war era. They found that those who performed better on intelligence tests tended to have more - and more mobile - sperm. The study