Angelfire

					           In my family there are many soft paws. Left handedness can be traced

back to my Great Grandfather, (II) and my mother's side of the family.          This

makes his genotype rr. His trait however was not passed on to my grandmother.

However I believe that my grandmother (112) became a carrier, or Rr, for this

gene. It is also possible that my grandfather (III)     may have been a carrier but it is

not certain. In my pedigree I assumed that he would have been. I assumed this

becauseone of my cousins (IV2) along with myself (IV6) is left-handed. In order

for this to be possible two out of six of his children would have been carriers.

           My Uncle Larry Ford (lIIl)   is a carrier for this gene (Rr) as is his wife.

Out of their two sons one was left-handed, IV2, while the other, IV3 was not

Tyrone (IV2) is left-handed or rr. His son Seth,V2 is also left handed (rr) while

his son Gabriel, VI, is not. The fact that Tyrone was able to pass his left handed

gene on to his son rules out the possibility of this trait being either X-Linked

Recessive or X-Iinked Dominant          My cousin Marion (IV3) who is Tyrone's

(IV2) brother has one affected daughter (V4), or rr, out of three children. All

three are girls.   This means that both MarIon and his wife Kristin (IV4) had to be

carriers   (Rr).




           This brings me to my own family.    My father (1114)was left handed (rr:

and I, IV6, am also left-handed.                              a
                                    This makes my mother, m113, carrier for the

gene (Rr). My sister IV5, is however unaffected. There was no information

available for my dad's side of the family being that he is deceased

           My Aunt Dona (III5) married a left-handed man (III6).       Neither of the

two sons, IV7 and IV8 that they had was effected however. Jefferey (IV8),
        however has a son, Dylan, V6, who is left handed (rr). This means that Jetrs wife

        Star (IV9), Jeff (IV8), my Aunt Donna (1115), and her son David (IV7) are all

        carriers for the gene.

                    My Aunt Nancy, 1117,was also not affected with the left handedness.

        Nancy however married a soft paw (rr). Blaine, 1118,had a son (IVIO) from a first

        marriage who was left handed, however the child they had together, IVll,              is not.

        Given this information        I would assume that my Aunt is not a carrier for this gene

        and that she is RR but it isn't possible to know this information        unless my cousin

        Katie (IVll)      marries a right handed man who is not a carrier (RR) and they have

        no affected offspring. All would be genotype RR.

                    My Aunt Peg (1119)has two children (IV12 and IV13) and neither child is

        affected     with the gene.   There is not much I can assume from this however


        because little information      was available to me about the children's fathers. My

        Uncle Don (11113) has not produced any offspring to this point in his life so

        whether he is of the genotype RR or Rr in not known.

        I believe    that the trait of being left-handed   is Autosomal   Recessive.   I believe this


because many of the left-handed people in my family have parents who are right handed.

Both males and females in my family seem to share in the passing of the trait from one

generation to the next. This therefore rules out the possibility of it being a y-Iinked trait

or a sex influenced     trait


        I ruled out the possibility     of this being an Autosomal    Dominant    trait because if


this were the case an affected person must always have an affected parent. There are

only three cases where this is true in my family and 3 cases were this is not. Also a
person who is not left-handed can not passthe trait on if this were the case. It is quite

obvious from my pedigree that this is not the case.
    ~

    0




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