BICD 100 - Week 3 + overheads - BICD 100 Week 3 Handout...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
BICD 100 Week 3 Handout: Pedigrees Unfortunately (or fortunately?), genetic experiments cannot be applied to humans! Therefore, an extensive examination of family historical records is often required to elucidate the genetic basis of a particular human condition. - A pedigree is used to accurately depict genetic information in a shorthand form. On a pedigree, is male and is female. Darkened individuals ( ) are affected by the trait (diseased) while blank individuals ( ) are free of the trait (unaffected). Horizontal lines show crosses/sex/mating, and vertical lines show parental/offspring relationship. The top row depicts generation I, followed by subsequent generations in each lower row (II, III, IV and so on). Advice : - Pedigrees are generally straightforward problems that contain a very logical solution. However, it is easy to make careless mistakes , so analyze the problem carefully! assumptions often have to be made about the alleles of unaffected individuals, based on other information in the pedigree be careful not to assume too much or too little. when a problem asks to “identify the genotype of all known individuals”, make sure to look at each individual on the pedigree carefully. think about what is known about that individual, and whether you have enough evidence to unambiguously conclude which alleles they carry. since humans have low numbers of progeny , the inheritance of affected alleles will often not follow precise Mendelian ratios. more deviation is expected when looking at 5 human progeny, compared to looking at 1000 plant progeny. look for key hints in the question: if the problem states that the disease is “rare ”, then it is safe to assume that
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern