Chromosomal Abnormalities

A structure that carries genetic information What is a chromosome? A structure that carries genetic information

What should they look like? 46 Chromosomes total All are in pairs

What is a Chromosomal Abnormality? A missing, extra, or irregular portion of chromosomal DNA. It can be from an atypical number of chromosomes or a structural abnormality in one or more chromosomes.

Chromosomal Abnormality Simply put, this means that a person has either too much, or too little genetic information.

Why does this occur? a) Spontaneous mutation - a problem during the cell division phase (mitosis or meiosis) b) Inherited genes - receiving 2 copies of faulty genes from your parents

1) Atypical Number of Chromosomes How many chromosomes are we supposed to have in each set?

1) Atypical Number of Chromosomes What this means is that an individual either is: a) missing a chromosome from a pair or b) has more than two chromosomes in a set

2) Structural Abnormality This means that there is a problem with the chromosome itself: -part of the chromosome is missing -part of the chromosome is duplicated -part of the chromosome is upside down -part of a chromosome has attached itself to another

Resulting disorders

Turner Syndrome Karyotype Missing either part of all of an `X`chromosome

Turner Syndrome - puffiness or swelling of the hands and feet - extra skin on the neck (webbed neck) - puffiness or swelling of the hands and feet - skeletal abnormalities and shorter than others - heart defects -affects sexual development and reproduction - kidney problems - normal intelligence

Turner Syndrome -occurs during cell division -does not appeared to be related to family history -affects 1 in 2500 girls

Down Syndrome Extra chromosome on 21

Down Syndrome - flat facial features - small head and ears - short neck - bulging tongue - eyes that slant upward - oddly shaped ears - poor muscle tone

Down Syndrome respiratory infections heart defects hearing loss moderate to severe intellectual disability usually develop more slowly have trouble learning to walk, talk, and take care of themselves.

Down Syndrome Affects 1 of every 800-1000 babies The mutated chromosome usually comes from the mother

Down Syndrome

Missing genetic material on chromosome 7 Williams Syndrome Missing genetic material on chromosome 7 Deletion

Williams Syndrome -lack the elastin protein, which gives blood vessels their stretchiness -this causes problems with the heart and circulatory system -intellectual disability -inability to gain weight properly - hypersensitivity to loud noises and an outgoing personality

Williams Syndrome Affects 1 of every 10,000 babies -unusual facial features (small upturned nose, wide mouth, full lips, small chin, widely spaced teeth)

Caused by a deletion in Chromosome 5 Cri du Chat Syndrome Caused by a deletion in Chromosome 5

Cri du Chat Syndrome -caused by abnormal larynx development -the child has a high-pitched cry that sounds like a cat -intellectual disabilities -difficulty walking and talking

Cri du Chat Syndrome -Affects 1 in 20,000-50,000 babies -affected individuals normally have difficulty with language

Cri du Chat Syndrome https://www.youtube.com/watch?v=TYQrzFABQHQ

Determine the genetic makeup of an individual Activity Determine the genetic makeup of an individual