Heterozygotes for a loss of expression allele of the methyl CpG binding protein 2 (MECP2) gene can develop Rett syndrome, which affects about one in ten thousand people. Select all of the following that accurately describe the Rett associated allele of MECP2.
Group of answer choices
dominant negative
wildtype at organismal level
dominant gain-of-function
mutant at molecular level
not wildtype at organismal level
dominant loss-of-function
wildtype at molecular level
dominant haploinsufficiency
recessive loss of function
Rett's syndrome is an X- linked dominant disorder. One copy of the mutated allele is sufficient for the cause. one copy of the gene MECP2 becomes mutated and this mutation is dominant-negative causing neurological disorders in exclusively female children. Loss of function in one allele is dominant enough to cause this syndrome (dominant loss of function). The heterozygous condition in this disorder is a case of dominant haploinsufficiency as one functional copy of gene the is not sufficient to meet the normal protein function normally in a cell. A wild type phenotype refers to a natural condition that is more common. Rett's syndrome has a low frequency (1/10000) of occurrence so it is not a wild type at the organism level. In this case, the mutation occurs at the molecular level (at the level of DNA and protein) (mutant at the molecular level).
Heterozygotes for a loss of expression allele of the methyl CpG binding protein 2 (MECP2) gene...
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