Question

A researcher is creating pedigrees for a trait he suspects to be dominant in humans. what are some of the likely features of his pedigrees for families with this trait?

Answer 1

A feature of a pedigree that indicate that a certain trait is a dominant trait is that one of the parents always have to have the trait.

There are, however, autosomal dominance and X-linked dominance.

For an autosomal dominant trait: 
- Appears equally frequent in both sexes.
- Both sexes transmit the trait.
- Present in all generations.
- When one parent has the trait and the other doesn't, approximately half of the offspring will present the trait.

For a X-linked dominant trait: 
- Both male and females can present the trait, but more females usually present it.
- Sons with the trait always have a mother that presents the trait as well.
- Daughters with the trait always have either a mother or father that presents the trait, or both.
- Fathers with the trait always have daughters with the same trait.

Answer 2

Answer:  

The trait will be shown more frequently in the family pedigree. Rest of the characteristics will depend on whether it is an autosomal or X linked dominant trait.  

Explanation:  

A pedigree analysis is used to study inheritance of genes in a family. It is used for many purposes like finding out the genetic source of a disorder in family or predicting the trait outcome for future progeny based on status of family members. If it's a dominant trait, it would be expressed even with a single copy so such a pedigree shows the trait more frequently.

Further Explanation:

Autosomal dominant trait:  

• An autosomal dominant trait will express itself in both the sexes.  
• Both the sexes will pass on the trait.  
• Overall pedigree will have at least one affected member in every generation because it is dominant and sex independent.  
• If around half of the children are affected and one parent is unaffected that means other parent is affected and heterozygous for the trait .  

X-linked dominant trait:

• A X linked dominant trait will be more frequently presented by a female.  
• A son with the trait will always have a mother with the trait because he inherited X chromosome from the mother.  
• Daughter with the trait will have either one or both the parents affected by the trait.  
• Fathers who have this trait will always have daughters with this trait becuase they will pass surely one X chromosome to the daughter.

Learn More:  

about pedigree: brainly.com/question/2952835 ( answer by JcAlmighty )

about different type of traits:  brainly.com/question/7135379?section=similar  ( answer by Palmss24 )

Keywords: pedigree, autosomal dominant, X-linked dominant, trait