Q1) Which of the following exocrine glands are not obstructed in cystic fibrosis?
A. Sweat gland
B. Pancreas
C. Lung
D. All the above
ANSWER & EXPLANATION
Answer: A. Sweat gland
Explanation:Cystic fibrosis is an autosomal recessive disorder caused by an abnormal gene on the long arm of chromosome 7. Abnormal function of the epithelial chloride channel encoded by cystic fibrosis transmembrane conductance regulator gene on chromosome 7q 31.2. In apical exocrine glands of airway and GIT there is increased sodium and water uptake from the lumen. In sweat glands there is decreased reabsorption of sodium and chloride. There is excessive loss of salt in the sweat occurs in cystic fibrosis.
Q2) IBD1 locus for Crohn’s Disease is found on:
A. Chromosome 6
B. Chromosome 12q
C. Chromosome 16
D. Chromosome 11p
Answer: C. Chromosome 16
Explanation: > Specific genetic defects associated with Crohn’s disease in human patients are beginning to be defined. The presence of a locus on chromosome 16 (the so-called IBD1 locus) has been linked to Crohn’s disease
The IBD1 locus has been identified as the NOD2 gene. Persons with allelic variants on both chromosomes have a 40-fold relative risk of Crohn’s disease compared to those without variant > NOD2 genes. The relevance of this gene to the pathogenesis of Crohn’s disease is biologically plausible, as the protein product of the NOD2 gene mediates the innate immune response to microbial pathogens
Other putative IBD loci have been identified on other chromosomes (IBD2 on chromosome 12q and IBD3 on chromosome 6) and are under investigation
Reference: Tavakkoli A, Ashley SW, Zinner MJ. Small Intestine. In: Brunicardi F, Andersen DK, Billiar TR, Dunn DL, Hunter JG, Matthews JB, Pollock RE. eds. Schwartz’s Principles of Surgery, 10e. New York, NY: McGraw-Hill; 2014