cloning

The other use of the word cloning means to make a copy of an entire organism
as a reproductive strategy. When referring to a whole creature as opposed to
DNA, a clone is an organism that’s created via asexual reproduction, meaning
offspring are produced without the parent having sex first. Cloning occurs naturally
all the time in bacteria, plants, insects, fish, and lizards. For example,
one type of asexual reproduction is parthenogenesis, which occurs when a
female makes eggs that develop into offspring without being fertilized by a
male (for some of you female readers, I’m sure this sounds very appealing). So
if reproduction by cloning is a natural, normal biological process, what’s the
big deal with cloning organisms using technology?

Attack of the Clones

A clone is simply an identical copy. The word is used as both a verb, as in “to
clone” (make one) and a noun, as in “a clone” (have one or be one).
Genetically, the word clone can have two meanings. When geneticists talk
about cloning, they’re most often talking about copying some part of the DNA
(usually a gene). Geneticists clone DNA in the lab every day — the technology
is simple, routine, and unremarkable.

Cloning before Dolly: Working with sex cells

Experimental cloning started in the 1950s. In 1952, researchers transplanted
the nucleus from a frog embryo into a frog egg. This and subsequent experiments
were designed not to clone frogs but to discover the basis of totipotents.

cells rearrange

After a few more divisions, the cells rearrange into a three-layered ball called
a gastrula. The innermost layer of the gastrula is endoderm (literally “inner
skin”), the middle is mesoderm (“middle skin”), and the outermost is ectoderm
(“outer skin”). Each layer is composed of a batch of cells, so from the
gastrula stage onward, what cells turn into depends on which layer they start
out in. In other words, the cells are no longer totipotent; they have specific
functions.

therapeutic cloning

The promise of therapeutic cloning is that someday doctors will be able to
harvest your cells, use your DNA to make totipotent cells, and then use those
cells to cure your life-threatening disease or restore your damaged spinal
cord to full working order. Creating totipotent cells from nullipotent cells to
treat injury or disease is difficult and triggers significant ethical debates (see
“Weighing Both Sides of the Cloning Debate” later in this chapter). Realizing
the potential of therapeutic cloning may be a very long way off. Meanwhile,
reproductive cloning — the process of creating offspring asexually — is
already causing quite a stir. For a taste of some of the excitement, see the
sidebar “Aclone in the universe?”.

Artificial twinning

Artificial twinning is relatively simple and was first done successfully (in
sheep) in 1979. A single fertilized egg was used, meaning that the resulting
offspring was the result of sexual reproduction. Zygotes from normally fertilized
(sexually produced) eggs were harvested from ewes (female sheep). The
zygote was allowed to divide up to the 16-cell stage (see the “Cloning before
Dolly: Working with sex cells” section earlier in the chapter). The 16 cells
were then divided into two groups. The separate groups of cells went right on
dividing, and after they were implanted into the reproductive tract of the
ewe, they resulted in twins. The twins were genetically identical to each other
because they were produced from the same fertilized egg.

Skin Cancer

Skin Cancer
Skin cancer is a disease in which cancer cells grow in the tissues of the skin. There are two major groups: nonmelanoma and melanoma. Nonmelanoma skin cancers are by far the most common types of cancer, with more than 1 million new cases diagnosed annually, and most are highly curable. Melanoma is much less common, but more serious. Melanoma is highly curable in its early stages, but may spread to other parts of the body.

At Ohio State's Comprehensive Cancer Center – James Cancer Hospital and Solove Research Institute, we have skin cancer experts who have dedicated their lives to providing the best skin cancer research and treatment. With research and treatment areas under one roof, we are better able to apply research advances to patient care. Recent research advancements include:
A laboratory study led by Anne VanBuskirk, PhD, OSUCCC Immunology Program, to find immunological approaches to help organ transplant patients fight skin cancer, a disease to which they are highly susceptible.

Clinical trials directed by William Carson, MD, a surgical oncologist at The James and leader of the OSUCCC Immunology Program, and Michael Walker, MD, a surgical oncologist specializing in melanoma at The James, based on immunology and the promise of a “vaccine” to help slow or stop the growth of malignant melanoma.

A study examining the use of a newly developed, molecularly targeted drug designed to inhibit key cancer growth factors. Interim results suggest the drug may be helpful in controlling malignant melanoma, which typically responds poorly to traditional treatments with chemotherapy or radiation.