Lost without a trace - but researchers cracked the case
In 1965 a boy disappeared. Over 40 years later, researchers at Karolinska Institutet have helped to show what happened.
In 1965, a four year-old boy disappeared in northern Canada. They feared that the boy had drowned in the nearby river, but the body was never found. Three years later, a hunter found parts of a child's cranium downstream at the same river. However, the police investigation concluded that it could not be the same person, as it was concluded that the cranium was from a child about twice as old.
When the cranium was investigated again, a few years ago, Karolinska Institutet's researcher Kirsty Spalding was recruited to the case. Using Spalding's carbon dating method, the Canadian investigation discovered that the age of the cranium had been incorrectly assessed, and that it did indeed match the missing four year old. It could then be established that it really was the same person, through a mitochondrial DNA analysis. The case is one of more than a dozen where the method has been used alongside other techniques to identify deceased persons.
"The cases include both recent crimes and older, "cold cases" in Sweden, New Zealand and Canada. I am now getting calls from police in the USA, where there are many cold cases," says Kirsty Spalding.
The method utilises the fact that the amount of carbon-14 increased significantly between 1955 and 1963 due to the nuclear tests conducted in the atmosphere by the super powers. Since then the amount has slowly declined. By measuring the amount of carbon-14 in tooth enamel, it is therefore possible to conclude with a high degree of precision when the tooth was formed, and thus establish the year of birth.
"I developed the method with Professor Jonas Frisén over ten years ago, to study the creation of new brain cells. Today I use it to study the renewal of fat cells. The forensic applications are an exciting side project," Spalding says.
Text: Anders Nilsson. The article is also published in Medicinsk Vetenskap, nr 4, 2012