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Explain what HLA groups are, and their significance.

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Introduction

Explain what HLA groups are, and their significance. HLA stands for Human Leukocyte Antigen and is found on white blood cells, more specifically on chromosome 6. The HLA- group of an individual is determined by a combination of the three genes of the HLA- system, called A, B and C. Each loci on the antigen have a large number of alleles, which means that it is a huge number of combinations. ...read more.

Middle

This is not easy because of the variety. The importance is to find the 'best match'. What is meant by the "genetic lotto"? The " genetic lotto" is a constructed model that is used to illustrate the possible connections between HLA- A, B and C, ABO blood types, and rhesus positive and rhesus negative. There are approximately 2 million combinations. What factors limited the number of children born to a woman before the advent of modern contraceptive technology? ...read more.

Conclusion

Another reason was breastfeeding. After birth a women is temporally sterile for two months if breastfeeding is practiced. If breastfeeding is practiced, infertility will increase. If a woman for example breastfeed for a year, she is sterile for ca. 8 months, and if she breastfeed for 2 years she will be sterile for 18 months. This means that the woman will have children only every 36th month (compared to normal 18 months). The last factor is voluntary limitation. These three factors are obvious before the advent of modern contraceptive technology. Now contraception is the essential way of voluntary limiting pregnancy. ...read more.

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