Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report the development of a rapid nonradioactive technique for the genetic prediction of human disease and its diagnostic application to hemophilia A. This method is based on enzymatic amplification of short segments of human genes associated with inherited disorders. A novel feature of the procedure is the use of a heat-stable DNA polymerase, which allows the repeated rounds of DNA synthesis to proceed at 63 degrees C. The high sequence specificity of the amplification reaction at this elevated temperature permits restriction-site polymorphisms, contained in the amplified samples, to be analyzed by visual inspection of their digestion products on polyacrylamide gels. By means of this method, we have performed carrier detection and prenatal diagnosis of hemophilia in two families with use of the factor VIII intragenic polymorphisms identified by the restriction enzymes BclI and XbaI. Predictions can be made directly from chorionic villi, without previous DNA extraction, and fetal sex can be determined by amplification of sequences specific for the Y chromosome. Specific amplification of genomic sequences with heat-stable DNA polymerase is applicable to the diagnosis of a wide variety of inherited disorders. These include diseases diagnosed by restriction-site variation, such as Duchenne's muscular dystrophy and sickle cell anemia, those due to a collection of known mutations, such as beta-thalassemia, and those due to gene deletion, such as alpha-thalassemia.
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PMID:An improved method for prenatal diagnosis of genetic diseases by analysis of amplified DNA sequences. Application to hemophilia A. 365 65

Desire for a male child is common in many countries and cultures. It has been argued that development of a practical and reliable method of allowing parents to choose the sex of their children would reduce family size, and consequently, population growth. There are currently 2 methods of preselection of sex: one preselects the sex before conception by either preventing or facilitating ovum fertilization by the X-bearing or Y-bearing spermatozoa, and the other is selective pregnancy termination. However, current laws and medical ethics in many societies allow selective termination only in cases of serious sex-linked diseases such as muscular dystrophy. Techniques for influencing the sex ratio by altering the X and Y chromosome balance include separation of the ejaculated spermatozoa into X- and Y-enriched fractions before insemination, and altering the vaginal condition. Methods of altering the vaginal condition attempt to influence the sex ratio by changing or choosing the prevailing conditions in the female genital tract which favor 1 or the other sperm type. Timing of insemination (before or after ovulation) is the key concept, and to a lesser extent, certain coital positions. Since 1978, at least 20 studies have been reported to have differential effects on the sex ratio, depending on time of insemination in the reproductive cycle. However, most of the studies have poor methodology and their results are conflicting. Another recently proposed technique is by dietary manipulation. The rationale of the dietary method appears to be attempts to change the ionic milieu of the genital tract of the conceiving female. So far, all these methods have proved to be ineffective and impractical. Currently, not much is known about the basic physiology of sperm at and after ejaculation in a woman and their subsequent interaction with the ionic and hormonal milieu of her genital fluids. It appears unlikely that parents can preselect the sex of their child with certainty by an available technique other than selective abortion.
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PMID:Current sex pre-selection methods. 1226 95