ArticlesOrthostatic Intolerance Is Not Necessarily Related to a Specific Mutation (Ala457Pro) in the Human Norepinephrine Transporter Gene
Section snippets
Methods
From December 2000 to October 2001, we studied 46 soldiers from the Austrian Army who sought medical advice because of dizziness while standing. All patients had a medical check when entering the army several months before and had been found healthy. The patients did not exhibit symptoms of a systemic illness that might affect the autonomic nervous system and did not take medications. The Austrian Science Fund review board and the ethics committee of the university Vienna approved the study.
Results and Discussion
Basic characteristics of the 14 OI patients are presented in Table 1. Patients with OI exhibited a mean heart rate of 108 ± 7 beats/min and substantially higher plasma norepinephrine concentration in the upright position. These 14 patients with OI syndrome underwent direct DNA sequencing of exon 9 of the NET gene, with respect to the specific mutation (Ala457Pro). Figure 1 shows DNA sequence patterns of the identified mutant and of an investigated patient with OI.
The specific mutation could not
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