Final answer:
Patau's syndrome, or Trisomy 13, is a chromosomal disorder where individuals have an extra thirteenth chromosome, often leading to severe disabilities and a low rate of survival to adulthood. Karyotype analysis is used for diagnosis and the risk of trisomies increases with maternal age.
Step-by-step explanation:
Patau's Syndrome (Trisomy 13)
Patau's syndrome, also known as Trisomy 13, is a chromosomal disorder characterized by the presence of an extra thirteenth chromosome. Trisomy is the condition of having three copies of one chromosome instead of the usual two. Similar to Down syndrome, which is trisomy 21, Patau's syndrome occurs due to a nondisjunction event during meiosis where chromosome 13 fails to separate properly, leading to a fertilized egg with an extra chromosome. However, unlike Down syndrome, most individuals with Patau's syndrome do not survive to adulthood as it results in severe intellectual disability and physical abnormalities. Karyotype analysis, which is a visual presentation of all the chromosomes in a cell, is used to diagnose the syndrome. The frequency of having a child with a chromosomal disorder such as Patau's syndrome can increase with the birth parent's age, especially for women over the age of 35.
Trisomy 13 is considered one of the autosomal trisomies, and individuals affected by it often show significant physical and mental impairments. It is less common than Down syndrome but similarly results from chromosomal nondisjunction. Data from the American Family Physician indicates that maternal age is a significant factor affecting the incidence of trisomies, with the risk increasing dramatically in older mothers.