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Not all people having genetic tests are those identified as at increased risk by genetic screening. Some people will already know that they are at increased risk of passing on a genetic disorder from a previous affected pregnancy, from other family history, or from a genetic test undertaken on one or both of the parents. If both parents are known carriers of a recessive disorder, or if the woman carries the gene for an X-linked disorder or if either partner carries the gene for a dominant disorder, any future child will be at risk. Some of these people will opt for pre-natal genetic testing (Harris 1998).

It has been suggested that discussion of prenatal testing by expert health professionals may imply to the patients that it is necessary, desirable, and in the best interests of the future child and that, it should be accepted. Green and Statham (1996) noted that an important distinction between the views of obstetricians and patients about prenatal diagnosis is that the obstetricians saw the tests as a way of detecting abnormality, whereas parents saw them as offering reassurance. It is likely that this desire for reassurance influences many people?s decisions to undergo both screening and diagnostic tests and that they expect a favourable result, which can make it more difficult to cope with when an abnormality is detected. The British Medical Association (1998) suggest that it is important that pre-test counselling for genetic testing should include discussion of the worst case scenario, so that the patient is aware of the possible outcomes and has been able to consider them carefully before deciding whether or not to participate.

There are various types of genetic testing and during pregnancy, these diagnostic tests usually follow amniocentesis at around 16 week?s gestation. Chorionic villus sampling (CVS) can be carried out at around 10-12 week?s gestation although there are some additional risks, such as the increased risk of miscarriage, which needs to be balanced against the value of an earlier diagnosis. With the pre-implantation method, a limited amount of success has been reported with testing embryos for genetic disorders before implantation. It is technically possible to fertilise oocytes in vitro, remove one or two cells, and test them for a range of disorders. The early embryos continue to develop normally and those without the disorder maybe selected for replacement into the uterus for gestation. An even newer technique is in pre-conception diagnosis. Research is being undertaken into the removal of the polar body from the oocyte before fertilisation. It is suggested that an assessment of this material may eventually provide an effective method of determining the genetic constitution of the oocyte. Although research is continuing to develop methods of detecting genetic disorders at an earlier stage, the most feasible option for prenatal diagnosis now and for the foreseeable future, is testing during pregnancy (Russo and Cove 1995).

Amniocentesis and CVS can be used to diagnose the chromosomal sex/gender of the foetus. The phrase ?infertility treatment? has given way to ?assisted reproductive technology? (ART), the main emphasis of difference between these two phrases is that the former represents techniques for infertility and the danger of passing on genetic diseases only, whereas ART opens up new options to enable all people to ?engineer? their own reproductive lives, (Challoner, 1999).

An aspect of ART that is rapidly developing is sex/ gender selection, although in the United Kingdom choice is permitted only where a genetic disease is carried in a male line (Gosden, 1999). The desire, or in some cases pressure, to have a child of a particular sex/gender can be so great as to lead to late abortion or even infanticide. According to Gosden (1999) in humans, the ratio at birth is close to parity, about 105 boys for every 100 girls born. It was not until the turn of the last century, and the discovery of the sex chromosomes, that scientists came to understand how sex/gender is determined. The sex/gender of a baby is fixed according to whether a male or female sperm fertilises the egg. Half the sperm produced in each testis carry a Y chromosome, which is a short stretch of DNA carrying the genes needed to make the testes and produce sperm. The other half carries an X chromosome like the eggs. If sperm and egg meet by chance there should be an equal number of XY (male) and XX (female) embryos. The type of sperm therefore fixes the sex/gender of the embryo (BMA 1998).

There are various Assisted Reproductive Technologies in which to pre-select the sex/gender of a baby, pre-implantation genetic diagnosis provides a way to screen a selection of embryo?s produced by IVF, to analyse their genetic make-up. This can enable the transfer of only those embryos of a particular sex/gender, to help certain couples avoid passing on sex-linked genetic disorders (Challoner 1999).

There have been other more acceptable non-IVF methods of sex/gender selection, the most contemporary method was developed in 1998 and is named ?MicroSort? (sperm separation). It was developed by a geneticist called Edward Fugger at the Genetics and IVF Centre in Fairfax, USA. The high tech approach taken in MicroSort relies upon the fact that the X

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