Applications & Awareness in Technology

Autosomal disorders that do not follow Mendelian inheritance patterns are often categorized as complex or non-Mendelian disorders. Unlike classical Mendelian inheritance (dominant, recessive), these conditions arise from more intricate genetic mechanisms, which can include the following:

### 1. **Mitochondrial Inheritance:**

– **Mitochondrial DNA Mutations:** These disorders are passed down from the mother because mitochondria, which have their own DNA, are inherited maternally. An example is **Leber’s Hereditary Optic Neuropathy (LHON).**

### 2. **Multifactorial Inheritance:**

– **Complex Traits:** These involve interactions between multiple genes (polygenic) and environmental factors. Conditions like **Type 2 Diabetes**, **Heart Disease**, and **Cleft Lip/Palate** are influenced by both genetic predispositions and lifestyle or environmental factors.

### 3. **Genomic Imprinting:**

– **Imprinted Genes:** Certain genes are expressed in a parent-of-origin-specific manner. Disorders such as **Prader-Willi Syndrome** and **Angelman Syndrome** arise from the same genetic region on chromosome 15, but the disorder that manifests depends on whether the defective gene is inherited from the mother or the father.

### 4. **Trinucleotide Repeat Disorders:**

– **Expansion of DNA Repeats:** These involve the expansion of specific DNA sequences. Disorders like **Huntington’s Disease** and **Fragile X Syndrome** are caused by the abnormal repetition of trinucleotide sequences in the genome.

### 5. **Mosaicism:**

– **Somatic Mosaicism:** This occurs when some cells in the body have a different genetic makeup than others, leading to disorders that vary in severity depending on the distribution of the affected cells. An example is **McCune-Albright Syndrome**.

These non-Mendelian disorders are more complex in their inheritance patterns and may involve a combination of genetic, environmental, and stochastic factors. They often require more sophisticated approaches to diagnosis, risk assessment, and treatment.

DNA fingerprinting, also known as DNA profiling, is a molecular biology technique used to identify individuals based on their unique DNA characteristics. Developed in the 1980s by Sir Alec Jeffreys, this method analyzes specific regions of DNA that are highly variable among individuals, known as short tandem repeats (STRs) or variable number tandem repeats (VNTRs).

The process begins with the extraction of DNA from a biological sample, such as blood, saliva, or hair. The extracted DNA is then amplified using polymerase chain reaction (PCR) to create sufficient quantities for analysis. Scientists then examine specific loci on the DNA where variations occur, generating a pattern or “fingerprint.”

DNA fingerprinting has numerous applications, including criminal investigations, paternity testing, and identification of disaster victims. It provides a high level of accuracy and is considered more reliable than traditional fingerprinting methods. However, ethical considerations regarding privacy and consent arise, particularly concerning the storage and use of genetic information. Overall, DNA fingerprinting is a powerful tool that has revolutionized forensic science and genetic research, enabling precise identification and a deeper understanding of genetic relationships.