HMB265H1 Lecture Notes - Proband, Autosome, Zygosity
![HMB265H1 Full Course Notes](https://new-docs-thumbs.oneclass.com/doc_thumbnails/list_view/2695735-class-notes-ca-utsg-hmb-265h1-lecture25.jpg)
25
HMB265H1 Full Course Notes
Verified Note
25 documents
Document Summary
Propositus: in a human pedigree, the person which first came to the attention of the geneticists; usually the phenotype of the propositus exceptional in some way. To see single-gene inheritance the patterns in the pedigree have to be interpreted according to mendel"s law of segregation but humans -> few kids -> 3:1 ratios & 1:1 ratios not usually seen until many similar pedigrees are combined. The affected phenotype of an autosomal recessive disorder is inherited as a recessive allele unaffected allele = dominant allele. Disorder appears in the progeny of unaffected parents. Affected progeny include both males and females-> dealing with simple mendelian inheritance of a gene on an autosome rather than a gene on a sex chromosome. Shows up in groups of affected siblings; ppl earlier and later in the generation tend not to be affected. Inbreeding increases the chances that two heterozygotes will mate -> higher chance of producing recessive disorders.