2. SLE (Lupus). (Click
here for an article about lupus and genetics.)
3. Weight. (Click
here for an article about obesity and genetics.)
4. Eye Color. (Click
here for an article about eye color.)
5. Intelligence.
6. Skin Color.
7. Many forms of behavior.
Click
here to see Genetic Heterogeneity, Twinnings and Sibblings described by MITOPENCOURSEWARE.
Lecture 32. probability and pedigrees
In Mendel’s time he used statistics to account for his observations on his experiments on peas, and, thanks to the results he abtained, he could formulate his two famous laws of genetics-- the Law of segregation and the Law of independent assortment, which were based on statistical segregation ratio 3:1, 9:3:3:1, 1:1:1:1 etc…
Nowadays in genetic research and especially in medical genetic counseling, statistics is needed for calculating the risks of genetic diseases in human pedigrees. The risks in these cases are expressed in terms of so-called probability.
The probability of an event is the chance that it will happen. The probability of tossing a coin to land heads up is roughly ½.
The probability of an impossible event is 0.
the probability of a certain event is 1.
If the probability of event x is p then the probability of 'not x' is 1-p.
The probability of two independent events ocurring at the same time is the product of their two indivdual probabilities.
So, for example, in the cross above, in the F2 the
probability of a wrinkled seed is ¼; the probability of a green seed is also ¼, and the probability of being both green and wrinkled is therefore ¼ x ¼ = 1/16.
The probability of being not wrinkled (i.e. smooth) is 1-¼ = ¾. The probability of being both smooth and green is therefore ¾ x ¼ = 3/16 and so on.
In the
example below about the coefficient of inbreeding of children from first cousin marriages, we considered a number of probabilities of ½ which we multiplied together to reach a final probability of 1/16 that any gene was homozygous by descent.
Autosomal recessive
A recessive trait will only manifest itself when homozygous. If it is a severe condition, it will be unlikely that homozygotes will live to reproduce, and thus most occurrences of the condition will be in matings between two heterozygotes (or carriers). An autosomal recessive condition may be transmitted through a long line of carriers before, by ill chance, two carriers mate. Then there will be a ¼ chance that any child will be affected. The pedigree will therefore often only have one 'sibship' with affected members.
a) A 'typical' autosomal recessive pedigree and b) An autosomal pedigree with inbreeding If the parents are related to each other, perhaps by being cousins, there is an increased risk that any gene present in a child may have two alleles identical by descent. The degree of risk that both alleles of a pair in a person are descended from the same recent common ancestor is the degree of inbreeding of the person. Let us examine b) in the figure above.
Considering any child of a first cousin mating, we can trace through the pedigree the chance that the other allele is the same by common descent. Let us consider any child of generation IV, any gene which came from the father, III3 had a half chance of having come from grandmother II2, a further half chance of being also present in her sister, grandmother II4 a further half a chance of having been passed to mother III4 and finally a half chance of being transmitted into the same child we started from. A total risk of ½ x ½ x ½ x ½ = 1/16.
Questions & Answers
A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
