Saliva, Teeth, White Blood Cells, Feces, Bones, Urine, Hair with the root attached
Teeth, bones, white blood cells, saliva, urine, feces, and hair with the root attached would all have DNA. Hair that's been cut does NOT have DNA (no root with skin cells) and red blood cells have no nuclear DNA because they lack a nucleus.
So in this case, we need to look at the crime scene sample, and the only bands or the only short tandem repeats that are going to be informative are the ones that do not match the victim. So in this case, the top band on the knife does match the victim. It very well could be her blood. That's not gonna be helpful for us. When we look at the second band on the knife, we see that it is not one that is seen in the victim, but it is one that we can see in Suspect 1 and 2, but Suspect 3's bands are higher. Then we look at the third STR on the knife, and that matches the victim, so that will not be informative. The fourth band on the knife is this big thick band, and the only place we see that is on Suspect 2, so now we are sure that it's Suspect 2, but let's just keep going down. The fifth band, because we want to be sure, we want to look at enough of these so we know it is for sure Suspect 2, so everywhere that the victim and the crime scene don't match needs to match Suspect 2, and that would include the fifth band that lines up, and the sixth band also lines up, so we're pretty confident it's Suspect 2 here. It's definitely not 1 or 3 because they are not a match on those alleles that are informative in that the alleles on the crime scene evidence are different from the victim.
Assess family history and construct a pedigree.
Update the family history and pedigree at future appointments.
Ask sensitive and inclusive questions.
Be aware of financial, ethical, legal, and social issues that may arise.
Assess family history and construct a pedigree.- Yes
Update the family history and pedigree at future appointments.- Yes, if you see the same patient, you should definitely be doing that.
Ask sensitive and inclusive questions.-Absolutely. Don't make assumptions. Let the patients speak for themselves.
Ask leading questions that make assumptions about the patients.-No! That is the exact opposite of C, don't do that! You're UT Austin nurses- you're better than that.
Be aware of financial, ethical, legal, and social issues that may arise.-Absolutely.
Rely entirely on the genetic counselor for family history.- No, I just said that's part of your job.
Two parents have an autosomal dominant condition due to a single mutated gene, A.K.A., they're heterozygous, although the homozygous mutant genotype is survivable. What are the odds that their next pregnancy will be affected? Well, you're gonna need a Punnett square to figure this out. So, two heterozygous parents, so like a "Aa" across the top and the side. And then, you can combine those four different ways: "AA," "Aa," "Aa," "aa," so really three different ways with two copies of the "Aa" genotype. So, since you only need a single copy of a dominant mutation to get the disorder but to be survivable, three out of four Children, or seventy five percent of would be the percentage chance that the next pregnancy would result in the condition.
Is it autosomal dominant? Well, I do see that every affected person seems to have one affected relative, so that one could be right.
Is it autosomal recessive? Well, if that were the case, then we would have a lot of carriers; the boy the first generation would be a carrier, the first boy in the second generation would be a carrier, as would the wife at the end of the second generation. So, not the most likely because if it were autosomal recessive, we would need, yeah, a lot of carriers in this family. Could it be X-linked recessive? It can't be X-linked recessive because we have this affected daughter in the fourth generation with the arrow next to her, and if it were X-linked recessive, she would have two copies of the disease causing allele, in which case should have gotten one from her father, and he would have to be affected. Could it be X-linked dominant? Well, we're seeing on the second generation that last affected male has an affected son, and his wife is not affected, so it's not gonna be X-linked dominant because then that woman at the very end of generation two would need to be affected. It's not mitochondrial because we have affected mothers not passing it on to all their kids, and affected dads passing it onto their kids, so that's not possible. It's not Y-linked because it affects women in the pedigree. It's not impossible to tell the correct answer is: the most likely would be autosomal dominant. It does not skip generations, it affects males and females, and both men and women are passing it on to both sons and daughters, so the correct answer is Autosomal Dominant.
Is it autosomal recessive? Well, it definitely seems to be recessive because we're skipping the second generation, but I am seeing that there are carriers and that all of them are females, so that points me in a different direction, and that is X-linked recessive. I think that's more likely because we have an affected dad making carrier daughters, no carrier sons, and then those carrier daughters go on to have affected sons, or carrier daughters themselves. It's not autosomal dominant because it wouldn't skip generations, and it would affect females too. It's not mitochondrial because we've got dads passing it along.
It's not Y-linked because we do have some half-shaded in females, and they don't have any Y chromosomes, so the most likely answer here is X-linked recessive
Could this be autosomal recessive? Could be; we'd have a whole lot of carriers though, so to have affected kids, we would need to have the person in the first generation who's a male be a carrier, as well as the second generation, first male and the last female, but it's not necessarily ruled out.
Could it be X-linked recessive? This one it could not be, and the reason we can tell is this individual in the third generation, the first female who has the arrow pointing to her, she has two recessive, disease causing mutations, and so she would need to get one from mom, and one from dad, and if dad had a single mutation he would be affected. He's not, so it cannot be X-linked recessive. Could it be X-linked dominant? Well, it can't be X-linked dominant because then the male in the third generation at the end of the pedigree, he would have had to have an affected mother because he's got one X, he gets it from her. She's healthy; it can't be X-linked dominant.
Mitochondrial; this doesn't look like that at all. We see dad's passing it on, affected mothers with some unaffected kids; it's not Y-linked because we see women in the pedigree with it, so this one could not be Y-linked recessive. It could not be X-linked dominant, it could not be mitochondrial, and could not be Y-linked, but it could be any other mode of inheritance. It's most likely to be autosomal dominant because we see a transmission from mother to sons and daughters; dads can pass it on to their sons, as well as their daughters; we don't see any skipping generations; and it occurs in about equal frequency in males and females, so autosomal dominant is most likely. But it cannot be X-linked recessive, X-linked dominant, or mitochondrial, or Y-linked, so the correct answers are: X-linked recessive, X-linked dominant, mitochondrial, and Y-linked.
Autosomal recessive? Well, it could be autosomal recessive potentially; we'd have a lot of carriers, and it's unlikely that we'd have more affected males than females, but it could be autosomal recessive. There's no deal breakers. What about X-linked recessive? That's what's most likely because we've got dads giving it to carrier daughters, and seeing the reemergence in sons with a single copy. Autosomal dominant? It can't be this one because we wouldn't be skipping the second generation. X-linked dominant? It can't be this one because A) we wouldn't skip generations, and B) every affected son would have an affected mother, which we don't see. It can't be mitochondrial because we don't have affected daughters at all, let alone passing it on to all their kids. It can't be Y-linked because we do see female carriers, so the correct answer for this one is:Autosomal dominant, X-linked dominant, Mitochondrial, and Y-linked is what it cannot be.
Autosomal recessive? The only way we can rule this one out is if we have two affected parents who have unaffected kids, which we're not seeing, so we can't eliminate that one, but it's not likely because we're not skipping generations. Could it be X-linked recessive? Well, if it were X-linked recessive then we would have the affected mother in generation two, would have two mutant copies, and therefore all of her sons would need to have the disorder, but she's got that first son who doesn't have it, so can't be X-linked recessive. Autosomal dominant? We can't rule that one out because it does go in every generation. It's more likely to be X-linked dominant based on what we're seeing in this particular family, so we can't rule that one out, and that's the right answer. Mitochondrial? It's not that one because we've got affected daughters who pass it onto only some children, and affected sons passing it on. It's not Y-linked because we have affected females. So, this one cannot be X-linked recessive, mitochondrial or Y-linked