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The gene controlling the Xg blood group alleles (Xg+ and Xg−) and the gene controlling a newly described form of inherited recessive muscle weakness called episodic muscle weakness (EMWX) (Ryan et al., 1999) are closely linked on the X chromosome in humans at position Xp22.3 (the tip of the short arm). A male with EMWX who is Xg− marries a woman who is Xg+, and they have eight daughters and one son, all of whom are normal for muscle function, the male being Xg+ and all the daughters being heterozygous at both the EMWX and Xg loci. Following is a table that lists three of the daughters with the
- (a) Create a pedigree that represents all data stated above and in the following table.
- (b) For each of the offspring, indicate whether or not a crossover was required to produce the phenotypes that are given.
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Concepts of Genetics Plus Mastering Genetics with Pearson eText -- Access Card Package (12th Edition) (What's New in Genetics)
- A specific human individual with a male sex has the same sex chromosome complement as a metafemale Drosophila fly. Both individuals have a diploid set of autosomes.i) What is the sex chromosome complement of these two individuals? ii) If these individuals were produced from a fertilization event involving an abnormal egg and abnormal sperm cell, provide the genetic make-up of the two gametes? Clearly indicate the male and female gametes.arrow_forwardIn humans, chromosome 16 sometimes has a heavily stained area near the centromere. This feature can be seen in a microscope, but otherwise has no effect on the phenotype of the person carrying it. When such a “blob" exists on a given copy of chromosome 16, it is a constant feature of that chromosome and is inherited. A couple conceived a child, but the fetus had multiple abnormalities and was miscarried. e.g., The fetus had three copies of chromosome 16, where 2 of the 3 copies of chromosome 16 had large blobs. Both of the mother's copies of chromosome 16 lacked blobs, but the father was heterozygous for blobs. The fetus was formed from a fertilization event that included a gamete produced by the in which nondisjunction occurred during the meiotic division. Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a mother; first. mother; second. father; first. C Your answer d father; second. E3 Fullso L e Insufficient information is provided…arrow_forwardIn a human genetic study, a family with five phenotypicallynormal children was investigated. Two children were “homozygous”for a Robertsonian translocation between chromosomes19 and 20 (they contained two identical copies of the fusedchromosome). They have only 44 chromosomes but a completegenetic complement. Three of the children were “heterozygous”for the translocation and contained 45 chromosomes,with one translocated chromosome plus a normal copy of bothchromosomes 19 and 20. Two other pregnancies resulted instillbirths. It was later discovered that the parents were firstcousins. Based on this information, determine the chromosomecompositions of the parents. What led to the stillbirths? Whywas the discovery that the parents were first cousins a key pieceof information in understanding the genetics of this family?arrow_forward
- Cat fur coat color genetics is interesting. Orange fur is dominant (''B'') to black fur (''b'') and piebald, which is white spotting, is dominant (''S'') to non-white-spotted (''s''). Both of those genes are located on the X chromosome. In addition, in cats, somatic cells exhibit X-inactivation randomly, which explains why there are tortoiseshell cats (when heterozygous, have orange and black spots) as well as calico cats (orange and black but also with white spots). An orange and white spotted male is mated with a tortoiseshell female. State the genotype of the male and the female.arrow_forwardCat fur coat color genetics is interesting. Orange fur is dominant (''B'') to black fur (''b'') and piebald, which is white spotting, is dominant (''S'') to non-white-spotted (''s''). Both of those genes are located on the X chromosome. In addition, in cats, somatic cells exhibit X-inactivation randomly, which explains why there are tortoiseshell cats (when heterozygous, have orange and black spots) as well as calico cats (orange and black but also with white spots). An orange and white spotted male is mated with a tortoiseshell female. Draw a dihybrid Punnet square to show the possible offspring:arrow_forwardInversions are known to affect crossing-over. The following homologs have the indicated order (the filled and open circles indicate centromeres): • (A B C D E) o (A D C B E) a. Considering the position of the centromere, what is this sort of inversion called?arrow_forward
- The genes for waltzer (v) and jittery (ji) are 18 map units apart on chromosome 10 in mice. A commercial establishment is maintaining a normal F1 group of mice carrying these genes in the cis configuration. An order arrives for 24 young mice each with waltzer, jittery, and waltzer + jittery. Let's assume that the average litter size is 7 offsprings , and including a 10% safety factor to ensure the recovery of the needed offspring, calculate the minimum number of females that need to be bred.arrow_forwardProduce a Punnett square to illustrate the dihybrid cross described below: There are two common alleles for the TAS2R38 gene on Chromosome 7. This gene encodes a seven-transmembrane G-protein coupled receptor. This receptor controls the ability to taste glucosinolates. Phenylthiocarbamide (PTC) is a synthetic glucosinolate. The recessive TAS2R38 allele produces a non-functional receptor. The father in this dihybrid cross is heterozygous for these alleles, meaning that he can taste PTC. The mother is homozygous recessive, meaning that she cannot taste PTC The father has X-Linked Protoporphyria which means that he is very sensitive to sunlight exposure, he is hemizygous for the dominant causative mutation. The mother is homozygous wild type at the same locus. Add a file here showing your diagram.arrow_forwardIn Drosophila, the genes for eye color, wing shape, and wing length are located on chromosome II. Purple eyes (pr), arc bent wings (a), and vestigial wings (vg) are the mutant forms of the wild type traits red eyes, straight wings, and long wings, respectively. You've discovered some data in your genetics laboratory which indicates that the distance between vg and pr is 12.5 m.u., the distance between a and pr is 44.7 m.u., and the distance between a and vg is 32.2 m.u. From this information, deduce the order of these genes on chromosome II and identify which gene is in the middle. A. a B. pr C. not enough information to tell D. vgarrow_forward
- An individual is heterozygous for a reciprocal translocation, with the following chromosomes: A • B C D E F A • B C V W X R ST • U D E F R ST • U V W X Q. Explain why the fertility of this individual is likely to be less than the fertility of an individual without a translocation.arrow_forwardA scientist working with Drosophila flies studies wing length, an X-linked characteristic. He has pure-breeding lines of short-winged and long-winged flies available. He decides to use reciprocal crosses for his work.i) What are reciprocal crosses? ii) Provide an example of the reciprocal crosses this scientist will do.iii) If the gene for wing length was sex-linked, but present in the pseudoautosomal region, what would you expect the outcome of a reciprocal cross to be with regards to males and females?arrow_forwardPlease take a look at the attachment.arrow_forward
- Human Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage LearningHuman Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning