Genes In Gender Development

Genes in gender development The typical human body has 23 chromosomes and each pair of chromosomes controls different aspects of development. However, the biological sex is determined by the 23rd pair. Chromosomes physically resemble the letters; XY for a male, and XX for a female. At 6 weeks, the SRY gene on the Y chromosome causes the gonads of the embryo to develop as testes. However, if the embryo has no Y chromosome, it will not have the SRY gene, so without this the gonads will develop as ovaries. However, sometimes the SRY gene is missing from the Y chromosome or doesn't activate. The foetus continues to grow and lives as a girl, but her chromosomes are XY, but there are no physical differences present. Koopman et al (1991) found that if female mice developed into male mice if the SRY gene was implanted. Furthermore, there are a number of conditions caused by abnormalities on the 23rd chromosome pair. These include, Turner's and Klienfelter's syndrome. The physical characteristics of someone with Turner's syndrome include: webbing of the skin, underdeveloped breasts and ovaries. Their psychological characteristics include: poor social and math skills but good verbal skills. The physical characteristics of someone with Klienfelter's syndrome include: underdeveloped testes and breast development. Their psychological characteristics include: poor language skills and a shy personality. A weakness of this theory is that it lacks in validity. This is because the psychologist needs to be sensitive towards people with either of these syndromes in order to not break ethical guidelines such as, protection of participant. Therefore, some questions that the psychologist wants to ask they cannot due to ethics, resulting in only gaining certain answers that could give bias results or an invalid picture of the syndromes. A strength is that chromosome testing on humans is reliable. This is because research is conducted in a lab were all extraneous variables are controlled therefore, cause and effect can be established. Also, a lab experiments use specialist equipment which implies that if the tests were redone, then the same results would be found, resulting in the method having high reliability. A weakness of research into chromosome testing such as, Koopman et al is that it was conducted on animals. Therefore, caution must be taken when extrapolating findings to humans. This is because, humans are very complex and have free-will, whereas animals are simple and act on instinct. The biological approach is reductionist. This is because it suggests that masculine and feminine behaviour is a result of having or missing the SRY gene1. However, it ignores important social influences such as, parental influences, who Faggot et al show to be highly influential on gender role development. The biological approach supports nature. It argues that one's biology can affect their behaviour e.g. Koopman's study shows that by adding the SRY gene to female mice, it can turn them male. However, it ignores nurture and the behaviourist theory that suggests that one learns behaviour from the environment through observation, modelling and copy and imitate. The biological approach supports determinism. This is because, it believes that gender related behaviour is biologically determined by genes. However, it ignores free-will and individual differences e.g. tomboys who through their own choice, deviate away from their gender's typical behaviour.