In this article, we will discuss about the inheritance patterns of genetic diseases. Several inheritance patterns such as autosomal recessive and dominant, X-linked recessive and dominant describe disease inheritance. Some traits are dominant in males and females and some are recessive. For instance: Hemophilia is dominant in males and recessive in females. Similarly, milk production is dominant in females and recessive in males. We will also describe the sex-linked and sex-influenced traits.
INTRODUCTION OF INHERITANCE PATTERNS OF GENETIC DISEASES:
Genetic diseases can be inherited from an affected individual to their offspring. The passing down of genetic disorders follows specific patterns that can be traced through generations. Understanding these inheritance patterns is crucial for genetic counselors and healthcare professionals to provide accurate diagnoses, manage risks, and offer appropriate treatments. In this article, we will explore the different inheritance patterns of genetic diseases along with real-life examples and references to support our understanding. https://www.ncbi.nlm.nih.gov/books/NBK115561
TYPES OF INHERITANCE PATTERNS OF GENETIC DISEASES:
AUTOSOMAL DOMINANT INHERITANCE:
In autosomal dominant inheritance, a single copy of an abnormal gene from one affected parent is sufficient to cause the disease in an offspring. The affected gene is typically located on one of the 22 pairs of autosomes, rather than the sex chromosomes. Example: Huntington’s disease is a classic example of autosomal dominant inheritance. The abnormal HTT gene is responsible for this degenerative neurological disorder.
2. AUTOSOMAL RECESSIVE INHERITANCE:
For autosomal recessive inheritance, both copies of a gene (one from each parent) must be abnormal for the disease to manifest. Carriers, individuals with one copy of the abnormal gene, typically do not show any signs of the disease but can pass it on to their children. Example: Cystic fibrosis is an autosomal recessive disorder caused by mutations in the CFTR gene, affecting the production of mucus and enzymes.
3. X-LINKED INHERITANCE:
4. Y-LINKED INHERITANCE:
Understanding the inheritance patterns of genetic diseases is vital for accurate diagnoses, effective management, and counseling for affected individuals, families, and healthcare professionals. Autosomal dominant, autosomal recessive, X-linked, and Y-linked patterns are the main classification systems. By considering the inheritance patterns and appropriate genetic testing, healthcare professionals can provide comprehensive care and offer the best guidance to patients and their families.
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Y-linked inheritance is exclusive to males, as Y chromosomes are only passed from father to son. Any genetic diseases associated with the Y chromosome are inherited from the father.
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