BB lecture 1-30-09 human inheritance, pedigrees

BB lecture 1-30-09 human inheritance, pedigrees - Chapter...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 14 (concluding) and Chapter 15 ( REVISED pp289-292; 297-301 ) Learning objectives: • Be able to construct/analyze a pedigree to deduce genotypes. • Know examples of how different human traits and certain disorders are inherited • Explain X-chromosome inactivation • Fetal testing: Distinguish between amniocentesis and chorionic villus sampling
Background image of page 1

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

View Full DocumentRight Arrow Icon
Making and using pedigrees to discern genotypes Ww ww ww Ww ww Ww Ww ww ww Ww WW or Ww ww First generation (grandparents) Second generation (parents plus aunts and uncles) Third generation (two sisters) Ff Ff ff Ff ff Ff Ff ff Ff FF or Ff ff FF or Ff Widow’s peak No Widow’s peak Attached earlobe Free earlobe (a) Dominant trait (widow’s peak) (b) Recessive trait (attached earlobe)
Background image of page 2
Autosomal dominant? Autosomal recessive?
Background image of page 3

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

View Full DocumentRight Arrow Icon
Autosomal dominant? Autosomal recessive?
Background image of page 4
The difference in sexes: The Sex Chromosomes Sex chromosomes: A female has two “X” chromosomes, and thus can carry two alleles of a gene. A male has only one “X” chromosome, and thus only has one allele. The male’s “Y” chromosome is homologous w/ the “X” only at the tips because of its small size compared to the much larger “X” Sex determination comes from the SRY gene located on the Y chromosome A human karyotype of 22 autosomal chromosome pairs, + the pair of sex chromosomes
Background image of page 5

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

View Full DocumentRight Arrow Icon
Some disorders caused by recessive alleles on the X chromosome in humans: Color blindness Duchenne muscular dystrophy Hemophilia Androgen insensitivity syndrome
Background image of page 6
The gene for color vision is on the “X” chromosome. A lack of color vision (aka ‘color-blindness’) is caused by a recessive allele . The following link shows patterns for testing for color vision. http://www.toledo-bend.com/colorblind/Ishihara.html
Background image of page 7

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

View Full DocumentRight Arrow Icon
Duchenne muscular dystrophy Definition - One of nine types of muscular dystrophy, a group of genetic, degenerative diseases primarily affecting voluntary muscles. Cause
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/26/2009 for the course BIO 311D taught by Professor Reichler during the Spring '08 term at University of Texas at Austin.

Page1 / 24

BB lecture 1-30-09 human inheritance, pedigrees - Chapter...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online