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It was in 1996 the world woke up to the news of a sheep named Dolly created through a technique called cloning. Dolly was a carbon copy of another sheep and this started a debate on should scientists be acting like God and producing animals and humans on order.

Cloning is done by removal of DNA from an ovum and replacing it with the DNA of an adult animal. The fertilized ovum is implanted in a womb and an identical or clone animal can be produced. However, the technique is fraught with risks. The cloned animals have been known to carry genetic disorders and have a comparatively short lifespans.

Not many people know that Dolly was not the first animal to have been cloned by scientists. Way back in 1958, scientist John Gurdon claimed to have cloned a frog by using intact nuclei from somatic cells of a Xenopus tadpole. In 1963, Chinese embryologist Tong Dizhou created the first fish clone by inserting the DNA from a male Asian carp into the egg of a female Asian carp. Dizhou went on to create the first interspecies carp clone by inserting Asian carp DNA into a European crucian carp in 1973. In 1986, a mouse named Masha became the first mammal to be cloned using embryo cell.

However, Dolly is still regarded as the most significant achievement in the history of cloning because she was the first mammal to have been cloned using adult cells. Before her, cells extracted from an embryo were being used to create a clone. The success of the Dolly experiment also resulted in a fierce competition among various research groups who started cloning one animal after another.

Scientists at the University of Hawaii created Cumulina, the first mouse clone using adult cells, within one year of Dolly’s birth in 1997.[ad#co-1]

The first cloned calf was also born in the same year and later kept at Minnesota Zoo Education Center. In 1999, Dr Xiangzhong (Jerry) Yang cloned a Holstein heifer named Amy by using ear skin cells from a high-merit cow named Aspen at the University of Connecticut. He followed it up by three additional clones, Betty, Cathy and Daisy in the same year.

The year 1999 saw birth of Second Chance, a Brahman bull which was cloned from a celebrity bull Chance at the Texas A&M University. The research centre was also successful in cloning a Black Angus bull named 86 Squared 15 using cells from his donor, Bull 86, which were frozen in 2000. Just like its parent, the cloned bull also exhibited natural resistance to tuberculosis, brucellosis, and other diseases which can be transmitted to meat.

Five Scottish piglets were created using cloning technique in 2000. In 2001, cloning was done to save Gaur, an endangered species of wild cattle. It was born from a surrogate domestic cow mother at the Trans Ova Genetics in Sioux Center, Iowa, USA. However, the clone died within two days.

The year 2001 saw intensified activity in the field of cloning with birth of two female jersey cows Millie and Emma at the University of Tennessee. They were the first cows to be produced using standard cell-culturing techniques.

In the same year a cat called CopyCat was cloned at Texas A&M University. Though the DNAs of both the clone and the host were same, they had different personalities. Around 10 more Jersey cows were cloned at the University of Tennessee in 2002 while the first commercially cloned cat, Little Nicky, was created by Genetic Savings & Clone in 2004.

In 2003, a Boer goat was cloned at Texas A&M University. In the same year, three male mules were cloned for the first time while a rabbit was also cloned in France.

The year also saw the birth of a first cloned deer named Dewey at Texas A&M University while in 2005 South Korean scientist Hwang Woo-Suk cloned the first dog, Snuppy, an afghan hound. South Korean scientists went on to clone sniffer dogs.

Anatolian Grey bull called Efe was cloned in Turkey along with world’s first buffalo calf through the “hand guided cloning technique” in the year 2009. Next year, the first Spanish fighting bull was cloned by Spanish scientists.

The cloning experiments on animals are still on around the world while there are some unverified claims of human cloning too.[ad#afterpost]

Can you roll your tongue into shape of a test tube? Do you get dry ear wax? Do you have cleft chin? Can you wiggle your ears? When you clasp your hands which thumb lands up on the top? These questions may seem innocuous and unwarranted but a whole lot of researchers are scratching their heads on these puzzles which many believe is linked to genetics.

So can you really roll your tongue into shape of a tube? Not many people can but then they do have friends who can and this difference some researchers say is because of genetics. Biology students are taught that tongue rolling is the simplest way to explain inherited genes. Those who can roll their tongues have inherited the gene from their tongue-rolling parents while those who can’t also have parents who can’t roll their tongues. You have got your genes from your parents and even if one of the parents has the tongue-rolling gene, you will be able to roll your tongue.

It’s not so easy to explain

The explanation is not as simple as it is made it out to be and your biology teacher might be wrong after all because there are people who can roll their tongues while their parents can’t. Another research study done by Matlock in 1952 concluded that identical twins don’t always share the tongue-rolling trait. Identical twins are known to have identical DNAs and hence should also share the ability to roll the tongue if they have same genes.  In 1975, another researcher demonstrated that identical twins are no more likely to share tongue-rolling than are fraternal twins. This gives birth to the idea that environment is also a major factor. Both the twins might be having the gene but it is not expressed in one of them due to absence of an environmental trigger.

The environmental trigger theory has also found takers in several other conditions like autoimmune disorders. People are known to be predisposed to them but these disorders are manifested in only those who encounter particular environmental triggers stress, pollution or specific disorders.[ad#co-1]

Another theory regarding tongue rolling is that there might be another gene called modifier gene which is controlling the expression of tongue rolling gene. So there can be parents who possess the gene to roll their tongues but still they can’t roll them because the modifier gene in them is off. Now their child can have the ability to roll the tongue if they modifier gene is not passed on.

All these explanations may seem confusing but that’s not the end of the whole story. Tomorrow some new research may prove that all the above propositions are wrong and there is some new factor that defines tongue rolling. Meanwhile, surveys done by biologists have put forth interesting data related to tongue rolling. It was found that in Spain 67 per cent of females can roll their tongues compared to just 64 per cent of the male population. However, Spanish men are better at wiggling their ears. Around 20 per cent of them can wiggle their ears as compared to 10 per cent of women. Another Iranian researcher found that north England does not have many people who can roll their tongues and this, he believes, is because of genetic intermingling with the Scandinavians.

Whatever the final verdict be, it’s clear that if you can roll your tongue, genetics are involved in this ability of yours. However, to what extent the power of genetics works in this scenario is not yet known. So, the picture is out but the contours are still being finalized.[ad#afterpost]