Biology 2581B Lecture Notes - Lecture 10: Sanger Sequencing, Dna Database, Expressed Sequence Tag

• School: Western University
• Department: Biology
• Course: Biology 2581B
• Professor: Susanne Kohalmi

Document Summary

Positional cloning involves finding the location of a gene based on its phenotype (a specific location for a specific gene) and can be done with (as in the cystic fibrosis example) and without (as in the hemophilia. In order to clone a gene without mapping information, we need information about family history and an idea = what might be causing the mutation and what its protein might be (biological as well as genetic information). Hemophilia a cloning & the blood clotting cascade: In this positional cloning example, we wish to find the gene causing hemophilia a, where patients of this disease fail to clot their blood (wounds keep on bleeding). In this same blood clotting cascade, coagulation factor ii (aka prothrombin) is cleaved to become thrombin (a serine protease), which then converts fibrinogen (soluble glycoprotein that doesn"t clot) to fibrin (insoluble fibre which does clot through cross-linkage).