Question

Use human genetics knowledge to answer the following questions (Please print):

1.(10) Is bipedalism a uniquely human trait? What makes us morphologically human and different? Expound on the uniqueness of humans compared to some of our closest relatives. Think behavior, neurological, social etc?

2.(10) Simple Mendelian disease was difficult to determine genetically. Using Tay Sachs disease, or another Mendelian disease that was not covered in class, tell me how it was discovered, when, what mode of inheritance it has, what gene causes it, how the gene was determined (if it is possible).

Answer 1

1. No, bipedalism is not a unique human trait. There are other organisms which are bipedled such as Ostrich (bird). It walks and runs on two legs (runs quite fast). Morphology is decided by the genotype. Hence we are imprints of what is coded through our genome. We are different from our nearest relatives of the animal world (apes, monkeys etc.) because, we have bigger brain capacities. Our brain is large with more association areas. Our relatives do not have larger capacities of brain. Neurology and the brain decides the behaviour of the organism. The social experiences are somewhat similar for us and our relatives. We are also very much prone to aggression and other harmful behaviours as it helps us in certain situations. Our basal instincts match to those whome we call "evolutionary backward" i.e. we also want to mate, keep ourselves fed and protected. But we something much extra such as creativity, or a desire to know about the world we live in. It keeps us moving forward.
2. Tay–Sachs disease is a genetic disorder that results in the degradation of nerve cells in the brain and spinal cord. Tay–Sachs disease is caused by a genetic mutation in the HEXA genes on chromosome 15. Tay–Sachs disease is an autosomal-recessive genetic disorder, meaning that when both parents are carriers, there is a 25% risk of giving birth to an affected child with each pregnancy. The affected child would have received a mutated copy of the gene from each parent. The disease is named after Waren Tay, who in 1881 first described a symptomatic red spot on the retina of the eye; and Bernard Sachs, who described in 1887 the cellular changes.