Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Example Input: Context: To establish a novel approach for quick and high throughput verification of human gene imprinting.', "By use of a pair of dye-labeled probes, 5' nuclease assay was combined with reverse transcriptase-PCR(RT-PCR) to genotype a coding single nucleotide polymorphism (cSNP), rs705(C/T) of a known imprinted gene, small nuclear ribonucleotide protein N (SNRPN), on both genomic DNA and cDNA of human lymphoblast cell lines.", 'Allele discrimination showed a clear monoallelic expression pattern of SNRPN, which was confirmed by RT-PCR based restriction fragment length polymorphisms. Pedigree analysis verified the paternal origin of expressed allele, which is in consistency with previous report.
Answer: Coding SNP is an ideal marker for detecting gene imprinting by 5' nuclease assay. This approach has also a potentiality to discover differential allele expression of non-imprinted genes in order to find gene cis-acting functional polymorphism.
Example Output: Is [ Coding single nucleotide polymorphism an ideal marker for detecting gene imprinting by 5 ' nuclease assay ]?

Example Input: Context: To survive and reproduce, animals must be able to modify their motor behavior in response to changes in the environment. We studied a complex behavior of Caenorhabditis elegans, male mating behavior, which provided a model for understanding motor behaviors at the genetic, molecular as well as circuit level. C. elegans male mating behavior consists of a series of six sub-steps: response to contact, backing, turning, vulva location, spicule insertion, and sperm transfer. The male tail contains most of the sensory structures required for mating, in addition to the copulatory structures, and thus to carry out the steps of mating behavior, the male must keep his tail in contact with the hermaphrodite. However, because the hermaphrodite does not play an active role in mating and continues moving, the male must modify his tail posture to maintain contact. We provide a better understanding of the molecular and neuro-muscular pathways that regulate male tail posture during mating.', 'Genetic and laser ablation analysis, in conjunction with behavioral assays were used to determine neurotransmitters, receptors, neurons and muscles required for the regulation of male tail posture. We showed that proper male tail posture is maintained by the coordinated activity of opposing muscle groups that curl the tail ventrally and dorsally. Specifically, acetylcholine regulates both ventral and dorsal curling of the male tail, partially through anthelmintic levamisole-sensitive, nicotinic receptor subunits. Male-specific muscles are required for acetylcholine-driven ventral curling of the male tail but dorsal curling requires the dorsal body wall muscles shared by males and hermaphrodites. Gamma-aminobutyric acid activity is required for both dorsal and ventral acetylcholine-induced curling of the male tail and an inhibitory gamma-aminobutyric acid receptor, UNC-49, prevents over-curling of the male tail during mating, suggesting that cross-inhibition of muscle groups helps maintain proper tail posture.
Answer: Our results demonstrated that coordination of opposing sex-specific and core muscle groups, through the activity of multiple neurotransmitters, is required for regulation of male tail posture during mating. We have provided a simple model for regulation of male tail posture that provides a foundation for studies of how genes, molecular pathways, and neural circuits contribute to sensory regulation of this motor behavior.
Example Output: Does coordination of opposing sex-specific and core muscle groups regulate male tail posture during Caenorhabditis elegans male mating behavior?

Example Input: Context: The clinical benefit of using reverse transcription polymerase chain reaction (RT-PCR)-based assays to detect circulating tumour cells during post-operative surveillance of cancer patients remains unclear. Cytokeratin 20 has been proposed as a tissue-specific marker for the detection of micrometastases in the blood of colorectal cancer patients. However, recent reports have challenged its specificity, and hence the validity of its use.', 'The aim of this study was to evaluate the tissue-specificity of ck20 mRNA transcription and its use for detecting circulating colon epithelial cells.', 'RNA was isolated from the peripheral blood of 51 colorectal cancer patients, four patients with benign gastrointestinal disease and 42 healthy controls. In addition, it was prepared from 32 colorectal cancers, from a pituitary cancer, from normal kidney, liver, fibroblasts, keratinocytes and from 24 lymph nodes obtained from eight patients with benign gastrointestinal disease. Real-time RT-PCR assays were used to quantitative and compare ck20 transcription.', 'Significant levels of ck20 mRNA were detected in all 42 blood samples from healthy volunteers and in all pre- and post-operative blood samples from colorectal cancer patients regardless of the presence of metastatic disease. It was also detected in all other mRNA samples analysed.
Answer: The lack of colon tissue-specificity renders ck20 useless as a marker for the post-operative surveillance of colorectal cancer patients.
Example Output:
Is cytokeratin 20 a tissue-specific marker for the detection of malignant epithelial cells in the blood of colorectal cancer patients?