Originally posted by icespeed
well, even in normal reproduction, genetic material can be lost (in fact, apparently one in every one hundred and fifty live births are genetically abnormal, which raises the question, how many of the miscarriages, which outnumber the live births, were abnormal?) so presumably the same can happen in cloning.
so when people say that the embryo is alive or viable, what exactly does that mean?
IIRC
Viable means the embryo would survive being born (able to live outside of the mother)
Alive... I can't actually find the medical definition / time for when an embryo/foetus is alive justnow. I think it is defined as the point when the brain has sufficiently developed as to be considered conscious. You can probably tell exactly what the contentious issue is there; we can't even define 'alive', so how can we decide when something is alive?
British legislation is
[q]Abortion in England, Scotland and Wales is governed by the Abortion Act 1967 as amended by the Human Fertilisation and Embryology Act 1990. This states that a registered medical practitioner may lawfully terminate a pregnancy, in an NHS hospital or on premises approved for this purpose, if two registered medical practitioners are of the opinion, formed in good faith:
"(a) that the pregnancy has not exceeded its twenty-fourth week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of the pregnant woman or any existing children of her family; or
(b) that the termination is necessary to prevent grave permanent injury to the physical or mental health of the pregnant woman; or
(c) that the continuance of the pregnancy would involve risk to the life of the pregnant woman, greater that if the pregnancy were terminated; or
(d) that there is a substantial risk that if the child were born it would suffer from such physical or mental abnormalities as to be seriously handicapped."
In addition, where a doctor "is of the opinion, formed in good faith, that the termination is immediately necessary to save the life or to prevent grave permanent injury to the physical or mental health of the pregnant woman" the opinion of a second registered medical practitioner is not required. Nor, in these limited circumstances, are there restrictions on where the procedure may be carried out.
The 1990 amendments to the Act removed preexisting links with the Infant Life Preservation Act 1929 which had made it illegal to "destroy the life of a child capable of being born alive" with an assumption that a child was capable of being born alive after 28 weeks gestation. Thus, terminations carried out under sections 1(1)(b) to 1(1)(d) of the Act may be performed at any gestational age.
The question of what constitutes a "serious handicap" under section 1(1)(d) is not addressed in the legislation. It is a matter of clinical judgment and accepted practice. In assessing the seriousness of a handicap, the following criteria may be used:
- the probability of effective treatment, either in utero or after birth;
- the child's probable potential for self-awareness and potential ability to communicate with others; and
- the suffering that would be experienced by the child when born or by the people caring for the child.[/q]
