Splice donor site

Mutations are either exonic or intronic. Missense, deletion and silent mutations are found in the coding region, with intronic mutations being located close to the splice-donor site of the intron following the alternatively... 

Answer D. At the 3 border of exon 2 with intron 2, a splice donor site is present. A mutation could cause exon skipping. Choices A, B, and C would not affect transcription or mRNA processing. 

Raida, M., Schwabe, W., Hausler, P., et al. (2001) Prevalence of a common fwint mutation in the dihydropyrimidine dehydrogenase (DPD) gene within the 5 -splice donor site of intron 14 in patients with severe 5-fluorouracil (5-FU)-related toxicity compared with controls. Clin. Cancer Res. 7, 2832-2839. 

Major splice donor site, used to form all spliced mRNAs... 

The IVS2+1G—>A mutation is a G-to-A change within the splice-donor site of intron 2, resulting in the deletion of the second exon from the mRNA. 

Another factor that regulates HDL cholesterol levels is the plasma level of cholesteryl ester transfer protein (CETP). CETP, a hydrophobic glycoprotein (M.W. 741,000), facilitates the transfer of cholesteryl esters in HDL and triacylglycerols in LDL and VLDL (see above). In CETP deficiency due to a point mutation (G A) in a splice donor site that prevents normal processing of mRNA, the plasma HDL cholesterol levels of affected individuals are markedly high, with decreased LDL cholesterol. In the affected families, there was no evidence of premature atherosclerosis and, in fact, there was a trend toward longevity. These observations support the role of CETP and the antiatherogenic property of HDL. However, not all factors that elevate HDL levels may be... 

Hellwinkel, O. J., et al., Complete androgen insensitivity caused by a splice donor site mutation in intron 2 of the human androgen receptor gene resulting in an exon 2-lacking transcript with premature stop-codon and reduced expression [published erratum appears in J Steroid Biochem Mol Biol 1999 Nov 71(1-2) 91]. J Steroid Biochem Mol Biol, 1999. 68(1-2) p. 1-9. 

Many mutations are known because of the relationship of the gene with congenital adrenal hyperplasia". These include a 5-base duplication and clusters of mutations in exons 6-8 (ref [1175]). The high similarity and proximity of the CYPllBl and CYPllBl genes appear to lead to mutant generated by unequal crossover and inactive chimeric product" " . Splice donor site mutations are also known" ". 

Conrad, R., Liou, R.F. Blumenthal, T. (1993) EMBOJ. 12, 1249-1255. Conversion of a rrara-spliced C. elegans gene into a conventional gene by introduction of a splice donor site. 

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