Molecular genetics mutations

Molecular Genetics Mutation Analysis in the Diagnosis of Metabolic Disorders... 

Another cumulative effect of radiation can be an irreversible alteration of DNA sequences. If part of a DNA molecule is ionized, its molecular chain may be broken. Chain breaks are repaired in the body, but after a serious rupture, the repaired unit may have a different sequence. This type of changed sequence is a genetic mutation. Altered DNA sequences in the reproductive organs are transmitted faithfully, thus passing on the genetic mutations to fiature generations. Because these effects are cumulative, individuals of childbearing age need to be especially carefial about radiation exposure. 

M5. Maekawa, M Sudo, K., Kanno, T., and Li, S. S.-L., Molecular characterization of genetic mutation in human lactate dehydrogenase-A (M) deficiency. Biochem. Biophys. Res. Commun. 168, 677-682 (1990). 

Jackson, I. J. (1991). Mouse coat colour mutations a molecular genetic resource which spans the centuries. BioEssays 13 439-446. 

Defects of complex II. These have not been fully characterized in the few reported patients, and the diagnosis has often been based solely on a decrease of succinate-cytochrome c reductase activity (Fig. 42-3). However, partial complex II deficiency was documented in muscle and cultured fibroblasts from two sisters with clinical and neuroradiological evidence of Leigh s syndrome, and molecular genetic analysis showed that both patients were homozygous for a point mutation in the flavoprotein subunit of the complex [17]. This was the first documentation of a molecular defect in the nuclear genome associated with a respiratory chain disorder. 

Hein DW. Molecular genetics and function of NAT1 and NAT2 role in aromatic amine metabolism and carcinogenesis. Mutat Res 2002 506-507 65-77. 

Nestorowicz, A., Wilson, B.A., Schoor, K. P., Inoue, H., Glaser, B., Landau, H., Stanley, C.A., Thornton, P.S., Clement, J. P., Bryan, J., Aguilar-Bryan, L. and Permutt, M.A. (1996) Mutations in the sulonylurea receptor gene are associated with familial hyperinsulinism in Ashkenazi Jews. Human Molecular Genetics, 5, 1813-1822. 

Once isolated, the natural H2 producers can be optimized by conventional mutagenesis, and they should be studied so that we can understand those features that make them the best H2 producers. This characterization would involve the analysis of metabolic fluxes (Stephanopoulos and Sinskey 1993 Schuster et al. 1999) and molecular genetics. It would result in new, previously unknown adaptations necessary for improved H2 production, and could provide information on the most important mutations that are required to obtain excellent H2 producers. Information obtained from these experiments should be used in genetic engineering approaches for optimizing H2 producers. Moreover, excellent H2 producers should be used in bioengineering approaches. 

Cleiren, E., Benichou, 0., VanHul, E., Gram, J., Bollerslev, J., Singer, F.R., Beaverson, K., Aledo, A., Whyte, M.P., Yoneyama, T., deVernejoul, M.C., and VanHul, W. (2001) Albers-Schonberg Disease (Autosomal Dominant Osteopetrosis type II) Results from Mutations in the C1CN7 Chloride Chaimel Gene. Human and Molecular Genetics 10, 2861-2867. 

Wang, Q., Shen, J.X., Li, Z.Z., Timothy, K Vincent, G.M., Priori, S.G., Schwartz, P.J. and Keating, M.T. (1995) Cardiac sodium-channel mutations in patients with long Qt syndrome. An inherited cardiac-arrhythmia. Human Molecular Genetics, 4, 1603—1607. 

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