Positional cloning identified the human homologue of the Drosophila patched (PTCH)gene as a candidate gene for the human disorder NBCCS or Gorlin syndrome.Screening of the patched coding region revealed a wide spectrum of mutations in NBCCS patients.Most of these mutations were predicted to result in premature protein truncation.What phenomenon would the researchers look for in the patients?
A)haploinsufficiency for the protein
B)recessive familial pattern of inheritance
C)predisposition to developmental abnormalities of the brain
D)incomplete formation of the forebrain
E)Shh mutations

Question

Quizplus · Accepted Answer

If most mutations in the patched gene result in premature protein truncation, then the researchers would expect to see haploinsufficiency for the protein in NBCCS patients. Haploinsufficiency is a phenomenon where a single functional copy of a gene is not sufficient to produce a normal phenotype, and is often observed in genetic disorders caused by loss-of-function mutations.

Positional Cloning Identified the Human Homologue of the Drosophila Patched