<prompt> True about Fragile X syndrome:Chromosomal breakingMitochondrial mutationTriplet nucleotide repeat sequenceCentrochrome absent  <response>: Fragile X syndrome is the prototype of the disease in which the mutation is characterized by a long repeating sequences of three nucleotides -Fragile sites are a region of the chromosome that show a tendency for separation, breakage or attenuation under particular growth conditions. One fragile site of a total of 120 in the human genome that has clinical significance is that on the distal long arm of chromosome Xql 7.3 associated with fragile syndrome-Nelson 18th515Fragile X Syndrome - Second most common genetic causes of mental retardation, after Down syndromeThe only distinctive feature that can be detected in at least 90 of postpubertal males with fragile -X Syndrome is macroorchidism Long face with a large mandible large everted ears Hyperextensible joints, a high arched palate mitral valve prolapsed is noted in some patients As with all X-linked disease fragile X syndrome affects males 