Untitled Quiz

Chromosome Mutations

• Chromosome mutations involve changes in the number or structure of chromosomes.
• Numerical mutations concern changes in the number of chromosomes.
• Structural mutations involve changes in the chromosome's structure.
• Abnormalities in sex chromosomes are another form of chromosome abnormality.

Numerical Chromosome Mutations

• Numerical abnormalities are a type of chromosome defect.
• These defects occur when there is a different number of chromosomes in the body cells from the typical 46 chromosomes.
• Instead of the usual 46 chromosomes in each cell, there could be 45 or 47.
• Monosomy, Trisomy, and Tetrasomy are types of numerical chromosome mutations.

Numerical Chromosome Syndromes

• Pallister-Killian Syndrome (PKS): A developmental disorder that affects many parts of the body, characterized by intellectual disability, sparse hair, unusual skin coloring, hypotonia (muscle weakness), and congenital diaphragmatic hernia. Associated with an isochromosome or extra copy of chromosome #12.
• Down Syndrome: A genetic disorder caused by the presence of all or part of a third copy of chromosome 21, resulting in mild to moderate intellectual disability, mental disorders, heart disease, thyroid disease, cancer (like leukemia), constipation, and imperforate anus.
• Patau Syndrome: A genetic disorder caused by an extra copy of chromosome 13. Severely affects the body, leading to early death (most babies die within six months), with features such as heart, respiratory, brain, eye, and hearing disabilities. Features include micrognathia and cleft plate or cleft lip.
• Edwards Syndrome: A genetic disorder caused by an extra copy of chromosome 18, resulting in severe disability and early death (usually within a week). Babies with the condition may have low birth weight, microcephaly (small head), micrognathia (small jaw), unusual hands/feet (clubfeet with overlapping fingers), feeding/breathing/seeing/hearing difficulties, heart/lung abnormalities, and umbilical hernia.

Oral Manifestations

• Down Syndrome: Possible oral manifestations include gingivitis, severe periodontal disease, early tooth loss, tooth erosion from alkaline saliva, loss of oral hygiene, and retained primary and permanent teeth in the mandible and maxilla.

• Patau Syndrome: Oral manifestations may include micrognathia and cleft palate or cleft lip.

• Edwards Syndrome: Oral manifestations may include cleft lip/palate, high-arched narrow palate, micrognathia, anterior open bite, posterior cross bite, and taurodontism.