Different icons represent different types of individuals. A diamond icon indicates an individual who is of unknown gender, a circle icon indicates a female individual, and a square icon indicates a male. Pedigree icons can also be used to indicate a person’s ancestry. The following example shows a pedigreed person with an ancestor who was born in the United States. This person has an American parent and an African-American parent.
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How do you know a pedigree is dominant or recessive?
The disease must be RECESSIVE if any affected individual has 2 unaffected parents. Since this is a genetic disease, at least one parent must have an allelic for the disease. The trait cannot be passed on to the child if neither parent is affected.
Affected individuals with a recessive trait have a 50% chance of passing it to their children. This means that if one affected parent has an affected allele and the other parent does not, only half of the offspring will be affected. The other half will not have the disorder.
How do you read a pedigree worksheet?
The circles are used to indicate females in a genealogy. The shape is darkened if the individual is affected by the trait. A marriage or union is indicated by a line between a male and female. The male and female are the parents according to the line drawn down from the marriage line.
Circles can also be used for males and females of the same species. For example, a circle can be drawn between two males, indicating that they are related to each other. This is called a “circled” pedigree. Circled pedigrees are often used by breeders to identify the parentage of their offspring.
What do the squares in a pedigree represent?
A male is represented by a square. The parents and their children are connected by a vertical line. A half-shaded circle or square indicates that a person is carrying the disease.
In the United States, the Centers for Disease Control and Prevention (CDC) and the National Institute of Allergy and Infectious Diseases (NIAID) are responsible for the surveillance of human immunodeficiency virus (HIV) infection in the U.S. population.
The National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, part of CDC, is the primary source of information on HIV infection and HIV-related health issues.
What does a triangle mean in a pedigree?
If the gender is not yet known, use a diamond, a circle or a square. A triangle is used when a pregnant woman is not carried to term. For women who have not given birth yet, include the estimated date of delivery. If you are pregnant, you may be asked to provide a sample of your blood or urine for testing.
If you do not have access to a blood sample, ask your health care provider for a urine sample. You will need to bring the sample with you to the appointment.
The sample will be tested for HIV, hepatitis B and C, and other sexually transmitted infections (STIs) and pregnancy-related STIs, including chlamydia, gonorrhea, trichomoniasis, syphilis, herpes simplex virus (HSV), and human papillomavirus (HPV). The results of the test will help you decide whether you should continue with your pregnancy or have an abortion.
For more information, visit the CDC’s website at www.cdc.gov.
What represents a male in a pedigree?
A male is represented by a square or the symbol ♂, a female by a circle or the symbol ♀. Mating is shown by a horizontal line connecting a male symbol and a female symbol; offspring symbols are connected in a row to the left and right of the male and female symbols, respectively.
Morphological differences between the two species can be seen in the shape of their genitalia. The male’s penis is longer and wider than the female’s, while the females’ clitoris is shorter and narrower. In addition, the males’ testes are larger than those of females, and the testicles of both sexes are covered with hair.
Is a males genotype XX or XY?
The biological sex of an individual is determined by the X and Y chromosomes, which come from the father and the mother. The Y and X chromosomes are also responsible for the development of male and female reproductive organs, including the testes, ovaries, and fallopian tubes, as well as for male sexual characteristics, such as facial hair and pubic hair.
How do you know if someone is a carrier on a pedigree?
Carriers are denoted by a dot in the center of the circle or square symbol; carrier status in a pedigree can also be depicted by shading half of the symbol. The double line indicates reproduction between first and second degree relatives. In the genealogical chart, this is followed by the paternal line, which is then traced through the male line and then the female line.
For example, if a man has two sons, one of whom is a first cousin of his father, he is said to have two first cousins. If he has a son who is also a second cousin, then he will have a third cousin and so on, until he reaches a fourth cousin.
What do squares and circles mean on a pedigree chart?
A diagram that shows the relationships within a family is used. A filled-in circle or square shows that the individual has the same trait with at least one other person in the family. This is called a linkage disequilibrium (LD), and it is a measure of the degree to which a trait is inherited from one generation to the next.
For example, if you have a child with a recessive trait, the child will not be able to pass that trait on to any of his or her siblings. If you are a parent, you can pass on your child’s trait to your children, but only if they are also affected by it.
The degree of LD between siblings is also called the linkage index (LI). However, LI can be as low as 0.5 or as high as 1, depending on the type of trait that is being passed on.
