" Mendel's Discovery and its importance to our insight about genes and genetic disorders."
INTRODUCTION
Gregor Mendel, a 19th century Czech monk who performed experiments with pea plants, is considered the "father of genetics." Mendel discovered the first laws of inheritance, which are the basic of modern genetics and our knowledge on genes and genetic diseases. Here we will discuss in detail Mendel's discovery about genetic disorders and its importance in our understanding.
EXPERIMENTS CONDUCTED BY MENDEL
Gregor Mendel experimented with cross-pollination of pea plants, wherein he investigated monirg and alleles for flower color, height,and seed shape. He observed what traits were passed on by each plant and its offspring, looking for inheritence patterns. Mendel in his experiments found out that fundamental laws of inheritance by following this:
1. The Law of Segregation:During the formation of gametes, the alleles for a trait separate from each other.
2. Second law of Mendel: The Law of Independent assortment, Genes for different characteristics are equally sorted from one paitn of gametes to another.
3. Law of Dominance: One allele; can be dominant over another allele, meaning the dominant allele appears in the phenotype.
MENDEL'S DISCOVERY AND ITS IMPORTANCE
The moment of discovery that laid the foundations of genetics: Mendel discovers the laws of inheritance. He laid the groundwork for how genes are inherited and expressed physically in an organism.
Mendel's insight into the basic laws of inheritance has been recognized traditionally as the founding moment of genetics. His work created a paradigm to conceptualize how genes are passed from generation to generation and affect the traits of an organism. Mendel's discovery is the background of genetics and his contribution to modern genetics in terms of gene/dna structure.
The Impact on Our Knowledge of Genetic Disorders
Mendel's work has a major influence on how we now understand genetic disorders. Scientists have been able to identify the genetic causes of many disorders by learning how traits are inherited and their expression in an organism as a result of the action of genes on each other. The result of this knowledge is the possibility of genetic testing in which people can find out whether they will likely inherit a certain genetic disorder. Moreover, Mendel's insight paved the way for gene therapy a treatment that uses genes to treat or prevent disease.
Genetic Disorders Trivia
1. Cystic Fibrosis:
– Genetic Disorder Causing Breathing & Digestion Issues
Cystic fibrosis (CF) is a genetic condition that impacts the respiratory and digestive systems. Caused by a cystic fibrosis transmembrane conductance regulator, CFTR gene mutation which is responsible for the creation of a proteins that controls salt and water transport within the body.
Symptoms:
1. Respiratory problems : Clogging of the lungs with thick, sticky mucus results in recurrent lung infections, wheezing and coughing.
2. Digestive problems: Mucus makes it difficult for enzymes involved in digestion to excreted properly through the GI tract leading to malabsorption of nutrients, leading to diarrhea and abdominal pain.
3. Growth and Development: Malabsorption of nutrients may cause growth delay
5. Reproductive problems: Men with CF are frequently infertile and women with CF are sometimes less fertile.
Treatment and Management:
1. Pill/ medications: Bronchodilators, antibiotics and mucolytics for the treatment of respiratory symptoms.
2. Physiotherapy: chest physiotherapy and reducing mucus for better lung function.
3. Nutritional support: Manage malabsorption through a high calorie diet and supplements
4. Lung Transplant:when all else fails.
Prognosis:
CF is a disease with no cure but treatment and management have extended appreciable life expectancy. Affected individuals have normal life expectancy if supported properly. You would need to be diagnosed early and treated well to manage disease control positively.
2. Sickle Cell Anemia :
Genetic Disease Interruption of Hemoglobin Production.
Sickle cell anemia (SCA) is a genetic disease which causes changes to hemoglobin, an essential cell component needed in order red blood cells deliver oxygen throughout the tissues.
Sickle cell anemia (SCA) is a condition caused by a genetic disorder of the hemoglobin, which is the molecule in red blood cells that carries oxygen through our body It is a result of a change (mutation) in the HBB gene that forms the beta-globulin subunit of hemoglobin.
Symptoms:
1. Anemia:they are malformed and are destroyed as such leading to a shortage of healthy red blood cells
2. Pain crises: blockages of sickle red cells in small blood vessels results in episodes of pain plus inflammation.
3. Susceptible to infections — Patients with SCA have a higher susceptibility to infections with Enterobacteria (i.e., encapsulated bacterial).
4. _Growth and development delayed: Anemia, chronic disease can cause delayed growth and development.
Working and Management:
1. Blood transfusions-- the frequency of these transfusions can boost the population of healthy red blood cells
2. Pain management: If you have severe pain crisis, the medications or other therapies that are available to ease them.
3. Antibiotics: Prophylactic antibiotics given preventatively.
4. Hydroxyurea: this drug can help lower the frequency of pain crises and spell anemia.
Prognosis:
SCA is a disease that has no cure, but treatment and management are advancing life expectancy to the state of primitive levels diseases. Those with SCA, when appropriately treated and followed can retain an excellent quality of life. Disease control and outcomes can be better managed with an early diagnosis, hence the importance of screening for this condition.
3. Huntington's Disease:
An Inherited Genetic Malfunction In The Brain
Huntington disease (HD) is an uncommon genetic disorder that results from a particular inherited disease affecting the brain — this cause damage to brain cells thus causing cognitive, motor, and psychiatric problems.
Causes:
HD is caused by a dilution of the CAG repeat in the Huntingtin gene that manifests as a neurotoxic protein disrupting brain cells.
Symptoms:
1. Motor symptoms: Chorea ( disorder of movement), rigidity and bradykinesia (slow movement)
2. Cognitive symptoms: Memory loss, impaired concentration and decision-making.
3. _Psychological symptoms: Depression, anxiety, mood changes, personality alterations
4. Symp.: Weight loss and nutrition problems: Eating difficulties, weight loss secondary to metabolic alterations
Stages:
1. Pre-symptomatic Stage: Genetic testing can detect those that are homozygous/uniparental disomy for HD gene.
2. Prodromal phase: This is the pre-morbid stage showing changes in mood and cognitive impairment.
3. Motor onset : Chorea/other motor manifstations
4. Final stage; severe cognitive, motor and psychiatric symptoms.
Treatment and Management:
There is no cure for HD, but medications can be used to manage the symptoms:
1. ^Medications : Anticholinergics or cholinesterase inhibitors for motor signs, antidepressants for psychiatric manifestations.
2. Physical therapy to help with mobility and balance.
3. Occupational therapy: to perform daily activities.
4. Social: for community support and guidance.
Prognosis:
The disease is progressive and the symptoms get progressively worse with time. After motor on-set the life expectancy is about 15-20 years. ..
Conclusion
The discovery of Mendel on the basic laws of inheritance has profound implication in gene and genetic disease. His work created so much of the foundation for modern genetics and was instrumental in DNA being sequenced and its structure identified. We still standing up to Mendel's discovery which is why using genetic testing and gene replacement therapy has become the norm for diagnosing & treating Genetic diseases. As we learn more and build on the knowledge of genetics, this is how we pay homage to Mendel and all the genetics scientist after him.