Quick questions on Reproductive cloning and genetic screening: VCE Biology Unit 2

Reproductive cloning produces a new organism that is genetically identical to an existing one. There are two main approaches:

Animal welfare: the high failure rate, miscarriages, malformed births and shortened lifespans raise welfare concerns.

Genetic screening is the testing of individuals or populations for specific genetic conditions or carrier status. It has several forms:

Informed consent. Patients should understand what the test reveals, its accuracy, and what options follow. Genetic counsellors are central.

A very early embryo (at the 2 to 8 cell stage) is mechanically divided into two or more pieces. Each piece, still composed of pluripotent cells, develops into a complete organism. The clones are genetically identical to each other (and to the original zygote) but their genomes came from the natural fertilisation, not from an existing adult.

The technique used to produce Dolly the sheep in 1996.

Testing the foetus during pregnancy.

Embryos created by IVF are tested at the 8-cell stage. Unaffected embryos are implanted. Used by couples at high risk of passing on a serious inherited condition.

A heel-prick blood sample taken from newborns. In Australia, the test screens for around 30 treatable conditions, including:

Tests adults for heterozygous carrier status of recessive disorders.

Testing healthy adults for late-onset diseases such as Huntington's disease, BRCA1/2 (breast and ovarian cancer risk), or familial cancers. Raises issues about how to act on the information.

Patients should understand what the test reveals, its accuracy, and what options follow. Genetic counsellors are central.

Genetic information about one person also reveals information about relatives. Family members may not want this information.

Insurance companies and employers could discriminate based on genetic information. Australia restricts insurer use of genetic results from research and certain predictive tests under a 2019 moratorium; legislation remains debated.

Parents may choose to terminate pregnancies after a prenatal diagnosis of conditions such as Down syndrome. This raises difficult questions about disability, eugenics and choice.