Human Genetics

Content
Human Genetics
Human chromosomes
Determination of sex
Sex linked inheritance
Chromosomal aberrations
Dizygotic and monozygotic twins
Inborn errors in metabolism
Sickle-cell anaemia
Genetic analysis through pedigree charts
Chromosome mapping in humans (including RFLPs, etc.)
Gene transfer in mammalian cells
Chromosome mediated gene transfer
Transformation of cells with free DNA
Use of human genetics in medical science 
Genetic counseling
Amniocentesis and antenatal diagnosis
Gene therapy
Making a choice of baby's sex
DNA fingerprinting in forensic science

In earlier topics of genetics on Biocyclopedia.com, more often examples like Drosophila were utilized to illustrate certain concepts. One would, however, like to study these concepts as illustrated by human beings, but man is rather unsuitable material for conventional genetic studies. Families are too small for dependable conclusions regarding phenotypic ratios; desired mating cannot be tried due to social implications and the life span is so long that it would take a long time in order to study even a few generations. Pedigree trees, therefore, were earlier utilized to study the genetics of various characters (see Mendel's Laws of Inheritance) and more recently cell cultures and molecular biology techniques were used for genetic analysis. Some of these aspects of human genetics will be discussed in this section.

 
A metaphase plate from leukocyte culture in human male showing 46 chromosomes, (obtained from Cytogenetics Laboratory, Zoology Department, B.H.U. Varanasi).
Fig. 24.1. A metaphase plate from leukocyte culture in human male showing 46 chromosomes, (obtained from Cytogenetics Laboratory, Zoology Department, B.H.U. Varanasi).