In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
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Question: Context: To describe a novel form of pontocerebellar hypoplasia (PCH) and map its genetic locus.', 'PCH is a heterogeneous group of disorders that are characterized by abnormally small cerebellum and brainstem. Autosomal recessive inheritance has been implied in many cases, but no genetic loci have been mapped to date.', 'The authors studied a consanguineous family from the Sultanate of Oman with three siblings with a novel form of PCH. The authors performed clinical studies and linkage analysis of this pedigree.', 'The clinical features of the affected children include developmental delay, progressive microcephaly with brachycephaly, seizures during the first year of life, hypotonia with hyperreflexia, short stature, and optic atrophy. Imaging studies showed a small pons and cerebellum, prominent sulci and lateral ventricles, and decreased cerebral white matter volume. A lack of dyskinesias distinguishes this pedigree from PCH type 2. Genetic studies of this family revealed evidence of significant linkage to chromosome 7q11-21 (maximum multipoint lod score 3.23).\Question: Does a novel form of pontocerebellar hypoplasia map to chromosome 7q11-21?

Answer: This pedigree represents a novel form of autosomal recessive PCH, which the authors propose to call cerebellar atrophy with progressive microcephaly (CLAM). This disorder maps to chromosome 7q11-21, and this locus was named CLAM. This report represents the first identification of a genetic locus for PCH.

Question: Context: Magnetic Resonance Imaging (MRI) allows a detailed "in vivo" macroscopic study of the human brain; previously, it has been demonstrated that Fluid Attenuated Inversion Recovery (FLAIR) sequence shows higher signal intensity of cortices belonging to limbic structures.', 'To measure and compare signal intensities (SI) of cytoarchitectonically different cortical regions.', 'In 22 adult subjects, without psychiatric or neurological diseases, FLAIR sequence was performed in coronal slices, perpendicular to the main hippocampal axis. Signal intensity was measured, with a region-of-interest (ROI) function, in 12 different cortical regions. We compared these values and grouped the cortices into five groups: (1) limbic cortices, (2) paralimbic agranular cortices, (3) paralimbic granular cortices, (4) parietal-type neopallium, (5) frontal-type neopallium. A t-test for comparison of paired samples was performed, considering p</=0.05 as statistically significant.', 'We found statistically significant differences amongst the different groups, with the exception of groups 1 and 2, which did not show differences between them. No statistically significant differences were found among cortices belonging to the same group.\Question: Does magnetic resonance imaging identify cytoarchitectonic subtypes of the normal human cerebral cortex?

Answer: Structural characteristics of the cerebral cortex cause changes in its signal intensity. Magnetic resonance imaging (FLAIR sequence) allows discrimination of different cytoarchitectonic areas of the human cerebral cortex.

Question: Context: Alternative splicing is an important mechanism for generating functional and evolutionary diversity of proteins in eukaryotes. Here, we studied the frequency and functionality of recently gained, rodent-specific alternative exons.', 'We projected the data about alternative splicing of mouse genes to the rat, human, and dog genomes, and identified exons conserved in the rat genome, but missing in more distant genomes. We estimated the frequency of rodent-specific exons while controlling for possible residual conservation of spurious exons. The frequency of rodent-specific exons is higher among predominantly skipped exons and exons disrupting the reading frame. Separation of all genes by the rate of sequence evolution and by gene families has demonstrated that rodent-specific cassette exons are more frequent in rapidly evolving genes and in rodent-specific paralogs.\Question: Are rodent-specific alternative exons more frequent in rapidly evolving genes and in paralogs?

Answer:
Thus we demonstrated that recently gained exons tend to occur in fast-evolving genes, and their inclusion rate tends to be lower than that of older exons. This agrees with the theory that gain of alternative exons is one of the major mechanisms of gene evolution.