Health bites

PUBLISHED : Tuesday, 15 January, 2013, 12:00am
UPDATED : Tuesday, 15 January, 2013, 9:45am

More strings attached Genetics researchers have identified 25 additional strings of DNA that could help predict whether a child has autism spectrum disorder. While rare, each of these DNA arrays - called copy number variations (CNVs) - have been found to double, at minimum, one's risk for the condition. This finding adds to another 31 CNVs previously reported to have the same high impact. Autism spectrum disorders are a group of neurodevelopmental disorders that impair verbal communication and social interaction, and affect behaviour. The research team, led by Dr Hakon Hakonarson of the Children's Hospital of Philadelphia, first analysed DNA from 55 individuals with multiple family members diagnosed with the condition, and identified 153 CNVs potentially specific to autism. The scientists then looked for these CNVs, along with another 185 previously identified CNVs, in 3,000 autism cases and 6,000 control subjects. The study was published yesterday in the journal PLoS ONE.

Mouth-watering possibility

Parkinson's disease is characterised by movement problems, but a study published today in Neurology finds that the condition often presents early on with non-motor symptoms, such as drooling, anxiety and constipation. "Often people with early Parkinson's don't even mention these symptoms to their doctors, and doctors don't ask about them, yet many times they can be treated effectively," says study author Tien K. Khoo of Newcastle University in Britain. The study screened 159 newly diagnosed Parkinson's patients and 99 people of similar ages who did not have the disease, for 30 non-motor symptoms. The patients had an average of eight non-motor problems, compared to three for the control group. A total of 56 per cent of patients had problems with excess saliva or drooling compared with 6 per cent in the control group; 42 per cent of patients had constipation compared with 7 per cent; and 43 per cent of patients had anxiety versus 10 per cent.

Teenage trysts of fate

Teenage girls who have been victims of abuse or neglect are more likely to have offline meetings with internet acquaintances - opening the door to potentially dangerous and risky situations, according to research in the journal Pediatrics. In the study of 251 girls aged between 14 and 17, 30 per cent reported having offline meetings. Abused or neglected teenage girls - who made up about half the participants - were more likely to present themselves online in a sexually provocative way than other teenage girls. And these types of online profiles are more likely to lead to offline meetings, says the study's lead author Jennie Noll, a psychologist at Cincinnati Children's Hospital Medical Centre. On the other hand, "high quality parenting" and parental monitoring helped reduce the association between adolescent risk factors and "high-risk" online behaviour, she says.

Blow and behold

Lung infections such as tuberculosis could soon be diagnosed in a matter of minutes, instead of days and weeks. A new study in the Journal of Breath Research has identified the chemical "fingerprints" given off by specific bacteria when present in the lungs. University of Vermont researchers were able to distinguish between different types of bacteria, as well as different strains of the same bacteria, in the lungs of mice by analysing the volatile organic compounds (VOCs) present in exhaled breath. They had infected the mice with Pseudomonas aeruginosa and Staphylococcus aureus, both of which are common in acute and chronic lung infections. The scientists hypothesise that bacteria in the lungs produce unique VOCs that are not found in regular human breath due to their differing metabolism. Breath-based diagnostics have also been investigated for multiple cancers, asthma and diabetes.