The completion of the Human Genome Project allowed deoxyribonucleic acid (DNA) sequencing information to be shared with the world; since that time the field of nutritional genomics has exploded. The importance of dietary choices on our health is becoming more apparent and identifying the relationship between genetics and nutrition is crucial to improving human health. The applications of nutrigenomics have begun to inform the use of dietary interventions and management strategies to impact disease states. This assignment will allow you to connect the field of nutrition with genetics and learn about a disease or disorder and how diet can affect the condition.
Select a diet-related disease to research and clearly identify the disease/disorder and how it relates to nutritional genomics. Write a 750- to 1000-word paper that includes the following:
Explain the causes and pre-disposing factors of your chosen disease.
Explain how the disease is diagnosed.
Describe common signs and symptoms of the disease.
Explain current treatments of the disease and describe the disease progression.
Research and describe the concept of nutritional genomics and the impact that diet has on the disease.
Prepare this assignment according to the guidelines found in the APA Style Guide, located in the Student Success Center.
Genetic Factors
Genetics plays a significant role in T2DM susceptibility. It is polygenic, meaning multiple genes contribute to risk.
Single Nucleotide Polymorphisms (SNPs): Over 100 genetic loci have been identified as risk factors for T2DM. Key genes include those involved in β-cell function, such as TCF7L2 (Transcription factor 7-like 2), which is the most strongly associated gene variant. TCF7L2 variants affect insulin secretion and glucose production.
Heredity: A strong family history significantly increases risk, indicating that inherited genetic predispositions affect how an individual processes glucose and fats.
Environmental and Lifestyle Factors
The genetic risk is primarily expressed when combined with specific environmental factors, forming the core of T2DM's etiology.
Obesity and Excess Adiposity: Especially visceral (abdominal) fat, which releases pro-inflammatory hormones (adipokines) that increase systemic insulin resistance.
Physical Inactivity: Low levels of exercise reduce glucose uptake by muscle cells, exacerbating insulin resistance.
Dietary Choices: A diet high in refined carbohydrates, saturated fats, and sugars contributes to chronic hyperglycemia and insulin overload, pushing β-cells toward exhaustion.
Age: Risk increases after age 45.
Diagnosis of T2DM
T2DM is typically diagnosed through blood tests that measure glucose levels. The primary diagnostic criteria, established by organizations like the American Diabetes Association (ADA), include:
| Test | Diagnostic Threshold | Description |
| Fasting Plasma Glucose (FPG) | ≥126 mg/dL | Blood glucose measured after an overnight fast (at least 8 hours). |
| Oral Glucose Tolerance Test (OGTT) | ≥200 mg/dL (2 hours post-load) | Measures blood glucose at intervals after the patient drinks a standard glucose solution. |
| Hemoglobin A1c (HbA1c) | ≥6.5% | Provides a measure of average blood glucose levels over the preceding 2–3 months. This is often the preferred initial test due to convenience. |
Export to Sheets
A diagnosis is typically confirmed by two abnormal results from the same sample or two separate test samples.
Common Signs and Symptoms
T2DM often develops slowly, and symptoms may be mild or even absent for many years, which contributes to late diagnosis. Common signs and symptoms include:
Polyuria (Frequent Urination): High glucose levels in the blood spill into the urine, pulling water with it.
Polydipsia (Increased Thirst): Due to fluid loss from frequent urination.
Polyphagia (Increased Hunger): Despite high blood glucose, cells are starved of energy because glucose cannot efficiently enter.
Unexplained Weight Loss: Occurs when the body, unable to use glucose, begins breaking down fat and muscle for energy.
Fatigue and Blurred Vision: Due to fluctuating blood glucose levels.
Slow-Healing Sores or Frequent Infections: High glucose impairs immune function and circulation.
Sample Answer
The explosion of nutritional genomics, or nutrigenomics, is fundamentally changing how we approach diet and disease management. For this analysis, I will research Type 2 Diabetes Mellitus (T2DM), a chronic metabolic disorder with a profound genetic component that is heavily influenced by diet and lifestyle.
Nutritional Genomics and Type 2 Diabetes Mellitus (T2DM)
Causes and Pre-disposing Factors of T2DM
Type 2 Diabetes Mellitus is a complex, multifactorial disease characterized by insulin resistance (the body's cells do not respond effectively to insulin) and a subsequent progressive failure of the pancreatic β-cells to produce enough insulin to overcome this resistance.