Can Autism spectrum disorders be diagnosed prenatally ??

Autism spectrum disorder (ASD) ::What is FISH??

·         What is the test   by which we do PCR ? In what suspected condition this is really helpful?? Such syndromes are Duchenne muscular dystrophy) for hemizygous deletion mutations (e.g., DMD deletions in males affected with  Duchenne muscular dystrophy): Williams syndrome, (2) carriers of an autosomal recessive disorder such as spinal muscular atrophy, and (3) carriers of an X-linked disorder such as Duchenne muscular dystrophy).

Terms Used on defects identified: : deletion; duplication; heterozygotePrincipk,e test and what it detects in a particular chromosome?? Ans:- Defects in a chromosome like deletion or duplication mutation can be deduced by comparing the amount of DNA or RNA in the patient sample with the amount of DNA or RNA in a control sample. It is FISH technology:   Previously, quantitative PCR determined the amount of product (DNA or RNA) at the completion of a set number of PCR cycles; however, this approach is not optimally reliable or accurate and has been largely replaced by "real-time" (also called "kinetic") quantitative PCR, in which the amount of product (DNA or RNA) is measured at the completion of each PCR cycle.

What do we, the clinicians mean by the very frequently used term “Real-Time Quantitative PCR” ??

Details of test principle of FISH ?? I. The DNA or RNA region of interest is amplified in the presence of a fluorescent probe or DNA-binding dye; the intensity of the fluorescent signal generated increases in proportion to the amount of PCR product produced.

II. The fluorescent signal intensity measured at the completion of each PCR cycle is graphed on an "amplification chart" to determine the C_T, defined as the point at which the fluorescent signal, i.e., PCR product, is first detected.