Age, Sex, and Gene Expression Score identifies a symptomatic, nondiabetic male patient as being at high risk of obstructive coronary artery disease

In October 2015, a 74-year-old Caucasian male patient (past medical history of hyperlipidemia, paroxysmal atrial fibrillation, hypertension, and hypothyroidism) presented to the cardiologist for follow-up outpatient evaluation of exertional chest pain. The patient had recently been seen at the Emergency Department for the same complaint. At that time, the patient’s cardiac markers, EKG, and pharmacological nuclear stress testing were all reported as normal. At presentation to the cardiologist, the patient’s physical examination findings were unremarkable. Over the course of the following year, repeat electrocardiograms and myocardial perfusion imaging studies demonstrated no evidence of ischemia. Despite the persistence of symptoms, the patient was reluctant to undergo invasive testing. The cardiologist ordered a simple blood test: the Age, Sex, and Gene Expression Score, which provides the current likelihood of obstructive coronary artery disease in nondiabetic patients. Based on the high Age, Sex, and Gene Expression Score result, the patient underwent invasive coronary angiography and a 98% stenotic lesion in the proximal left anterior descending artery was discovered. A drug-eluting coronary stent was placed and resulted in the complete resolution of the patient’s symptoms

Absence of duplication of chromosome 21 genes in familial and sporadic Alzheimer\u27s disease

The possibility that Alzheimer\u27s disease (AD) is caused by overexpression or duplication of one or more genes on chromosome 21 has been raised by the observation of AD-like neuropathologic changes in individuals with Down syndrome and by the mapping of both the defect for familial AD and the amyloid beta protein gene to this autosome. Possible duplication on chromosome 21 was investigated in both familial and sporadic AD by means of restriction fragment length polymorphisms for the amyloid and SODI loci, as well as for DNA markers in the vicinity of the familial AD defect and in the critical Down syndrome region of chromosome 21. No evidence of increased DNA dosage was observed in either brain or leukocytes of patients with inherited or sporadic forms of AD. Duplication of these regions is therefore not a frequent event in either form of AD. Furthermore, no significant allelic association was detected between AD and any of the loci, including the amyloid and SODI genes, providing no support for the hypothesis that defects in these specific genes are the primary cause of AD

The genetic defect causing familial Alzheimer\u27s disease maps on chromosome 21

Alzheimer\u27s disease is a leading cause of morbidity and mortality among the elderly. Several families have been described in which Alzheimer\u27s disease is caused by an autosomal dominant gene defect. The chromosomal location of this defective gene has been discovered by using genetic linkage to DNA markers on chromosome 21. The localization on chromosome 21 provides an explanation for the occurrence of Alzheimer\u27s disease-like pathology in Down syndrome. Isolation and characterization of the gene at this locus may yield new insights into the nature of the defect causing familial Alzheimer\u27s disease and possibly, into the etiology of all forms of Alzheimer\u27s disease