|Cumulina's second birthday|
Dr. Ryuzo Yanagimachi, head of "Project Yana" that produced Cumulina said: "We celebrated her first and second birthdays, I didn't expect a third birthday. She was special and was the only one given a name. The others have numbers."
|Rainbow, Allie and CC. (From left to right)|
In their first attempt to clone a cat, researchers obtained the cells used to make the clone from the skin cells of a donor cat. Eggs from other cats were used for the next step. Their chromosomes were removed and replaced with the DNA from the frozen cells, creating cloned embryos which were then transplanted into surrogate mothers. It resulted in cloned embryos that were transferred into seven recipient females. Only one cat became pregnant, with a single embryo. But this pregnancy was miscarried and the embryo was surgically removed after 44 days.
In the next attempt the scientists tried using cells from ovarian tissue to receive the DNA from the cat to be cloned. Five cloned embryos that were made in this way were implanted into a single surrogate mother. Pregnancy was confirmed by ultrasound after 22 days and CC was delivered 66 days after the embryo was transferred. The kitten was vigorous at birth and appeared to be completely normal.
The announcement of the successful cat cloning was not given until the animal had completed its shot series and its immune system was fully developed.
On 2003, a female horse was born in Italy from his surrogate mother, it was the first cloned horse and the first to be cloned and carried by its cloning mother (which was not planned and just a coincidence). The researchers technique was to fuse the nuclei of skin cells taken from one male Arabian thoroughbred horse and a one Haflinger mare with eggs taken from slaughtered abattoir horses and emptied of their own DNA. With this technique, they created 841 successfully reconstructed male and female embryos. Of that 841 embryos just eight male and fourteen female embryos developed after seven days of culture. And of the 17 embryos inserted into the mares, only four lead to pregnancies. The horse, called Prometea was born after 336 days and was the only one to survive. The researchers said that a possible application for this techniques could be breeding from castrated male horses that achieve success so the clone could then be used as a stud.
|Tai and Snuppy. (From left to right)|
. The reaserchers took the nucleus from the Afghan hound and placed it into an empty egg cell, that was then stimulated to start developing into an embryo that was later transferred to a yellow labrador. The scientists obtained only three pregnancies from more than 1,000 embryo transfers into 123 recipients. Of these three pregnancies, one miscarried and one died soon after birth.
Scientists hope dog clones will help them understand and treat a range of serious human diseases. "The dog has characteristics similar to human beings," told the lead researcher Hwang Woo-suk "some of their diseases are almost the same as human diseases."
Rosita carried cow genes and two human genes responsible of some proteins in human milk, and it's able to produce milk really similar to human milk. Rosita was cloned to help fighting infant mortality rate. “Our goal was to raise the nutritional value of cows’ milk by adding two human genes, the protein lactoferrin, which provides infants with anti-bacterial and anti-viral protection, and lysozyme, which is also an anti-bacterial agent.” said Adrian Mutto from the National University of San Martín.
By Juan Carlos Blanco, Paula Blanco, Javier Verde and Laura Corchado.