Account-creators
99
edits
Difference between revisions of "Libre Pathology talk:Study Group"
Jump to navigation
Jump to search
Libre Pathology talk:Study Group (view source)
Revision as of 01:04, 14 May 2015
, 01:04, 14 May 2015no edit summary
| Line 114: | Line 114: | ||
Robbins and Cotran Chapter 5 9th Edition: | |||
{{hidden|MC cause of spontaneous abortion is ?|<center>[[ A demonstrable chromosomal abnormality.]]</center>}} | |||
{{hidden|1% of all newborn infants possess a gross chromosomal abnormality and 5% of people <25y present with |<center>[[a genetic disease. ]]</center>}} | |||
{{hidden|Mutation|<center>[[permanent change in the DNA, if affect germ cells are transmitted to the progeny ]]</center>}} | |||
{{hidden|List and describe 4 broad categories of human genetic disorders:|<center>[[Disorders related to mutation sin single genes with large effects i. Usually follow classic Mendelian pattern of inheritance | |||
ii. Often highly penetrant (large proportion of pop with gene has disease) | |||
b. Chromosomal disorders | |||
i. Structural or numerical alterations in autosomes and sex chromosomes | |||
ii. Uncommon, high penetrance | |||
c. Complex multigenic disorders | |||
i. Interactions between multiple variant forms of genes and environmental factors (polymorphisms), poly genic means disease when many polymorphism present | |||
d. Single gene disorders with nonclassic patterns of inheritance (not mendelian) | |||
i. Disorders resulting from triplet repeat mutations | |||
ii. Mutations in mitochondrial DNA | |||
iii. Those influenced by genomic imprinting | |||
iv. Those influenced by gonadal mosaicism]]</center>}} | |||
{{hidden|List and describe the possible outcomes of a point mutation in a coding region?|<center>[[a. Missense mutation – pt mutation changes amino acid code, conservative when the amino acid is preserved, non conservative when replaced with another amino acid | |||
b. Nonsense mutation – makes a stop codon ]]</center>}} | |||
{{hidden|List and describe the possible outcomes of point mutation or deletion in a non-coding region.|<center>[[a. Promoters/enhancers – interfere with binding of transcription factors, marker reduction or total lack of transcription, b. Introns – defective splicing > failure to make mature RNA > no translation]]</center>}} | |||
{{hidden|List and describe the possible outcomes of deletions and insertions.|<center>[[a. Small coding: not multiple of three = frameshift, if multiple of 3 than add or del amino acids accordingly, often premature stop codon | |||
i. Tay Sachs disease: 4 base pair insertion in Hexosaminidase A gene | |||
{{hidden|List and describe the possible outcomes of trinucleotide repeat mutations. | |||
a. Usually G&C, dynamic and increase during gametogenesis, “RNA stutters” | |||
b. Fragile X – CGG 250-4000, Huntinton’s Disease * See Neuropath Notes | |||
{{hidden|List and describe three examples of inheritance of single gene mutations | |||
a. AD – manifested in the heterologous state, one parent of index case is usually affected, males and females affected and both can transmit condition | |||
i. De novo cases may not have affected parent | |||
ii. Penetrance = fraction of people with gene who have the trait | |||
iii. Variable expressivity = those with mutant gene have variety of phenotypes | |||
iv. Often age of onset is delayed so can reproduce before die from disease | |||
v. Biochem mechanisms | |||
1. Reduced production of a protein or dysfunctional/inactive protein | |||
2. Involved in regulation of complex metabolic pathyway subject to feedback inhibition | |||
3. Key structural proteins (collagen and cytoskeleton of RBC) | |||
a. May be a dominant negative , e.g. osteogenesis imperfecta | |||
4. Gain of function are rare, 2 forms | |||
a. Increased in proteins normal function (excess enzyme activity) | |||
b. Huntinton’s diseas (abn protein accumulates, toxic to neurons) | |||
b. AR | |||
i. Largest category – both alleles at a locus are mutated | |||
1. Expression is uniform, complete penetrance common, early onset, unaffected carrier family members, mostly enzymes | |||
c. X Linked | |||
i. All sex linked, and almost all are recessive , if Y Chromosome affected usually infertile males > no progeny | |||
ii. Male expression b/c hemizygous, daughter carriers with variable phenotype because of lionization of 2nd X e.g G6DP | |||
iii. Dominant . vitamin D resistant rickets]]</center>}} | |||
Stopped at P142 | |||
Molecular Genetic Diagnosis | |||
1. List three basic molecular diagnostic techniques | |||
a. Karyotyping | |||
b. Southern blot | |||
c. Sanger DNA sequencing | |||
d. Polymerase chain reaction | |||
2. Constitutional vs somatic mutaitons. | |||
Hi Michael, I've started, but mostly just with the questions for now, as I study I will keep working on it. Can you help me, maybe we can make additional discussion pages for each of my "study" exams,e.g. molecular, robbins chapters, cap protocols etc. | Hi Michael, I've started, but mostly just with the questions for now, as I study I will keep working on it. Can you help me, maybe we can make additional discussion pages for each of my "study" exams,e.g. molecular, robbins chapters, cap protocols etc. | ||