CASE STUDY |An unexpected outcome A newborn screening program identified a baby with a rare autosomal recessive disorder called arginosuccinate aciduria (AGA), which causes high levels of ammonia to accumulate in the blood. Symptoms usually appear in the first week after birth and can progress to include severe liver damage, developmental delay, and mental retardation. AGA occurs with a frequency of about 1 in 70,000 births. There is no history of this disorder in either the father's or mother's family. This case raises several questions: Since it appears that the unaffected parents are heterozygotes, would it be considered unusual that there would be no family history of the disorder? How would they be counseled about risks to future children?

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Answer 1

Textbook Question

Chapter 22, Problem 1CS

CASE STUDY |An unexpected outcome

A newborn screening program identified a baby with a rare autosomal recessive disorder called arginosuccinate aciduria (AGA), which causes high levels of ammonia to accumulate in the blood. Symptoms usually appear in the first week after birth and can progress to include severe liver damage, developmental delay, and mental retardation. AGA occurs with a frequency of about 1 in 70,000 births. There is no history of this disorder in either the father's or mother's family. This case raises several questions:

Since it appears that the unaffected parents are heterozygotes, would it be considered unusual that there would be no family history of the disorder? How would they be counseled about risks to future children?

Expert Solution & Answer

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

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Answer 2

Textbook Question

Chapter 22, Problem 1CS

CASE STUDY |An unexpected outcome

A newborn screening program identified a baby with a rare autosomal recessive disorder called arginosuccinate aciduria (AGA), which causes high levels of ammonia to accumulate in the blood. Symptoms usually appear in the first week after birth and can progress to include severe liver damage, developmental delay, and mental retardation. AGA occurs with a frequency of about 1 in 70,000 births. There is no history of this disorder in either the father's or mother's family. This case raises several questions:

Since it appears that the unaffected parents are heterozygotes, would it be considered unusual that there would be no family history of the disorder? How would they be counseled about risks to future children?

Expert Solution & Answer

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

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Answer 3

Textbook Question

Chapter 22, Problem 1CS

CASE STUDY |An unexpected outcome

A newborn screening program identified a baby with a rare autosomal recessive disorder called arginosuccinate aciduria (AGA), which causes high levels of ammonia to accumulate in the blood. Symptoms usually appear in the first week after birth and can progress to include severe liver damage, developmental delay, and mental retardation. AGA occurs with a frequency of about 1 in 70,000 births. There is no history of this disorder in either the father's or mother's family. This case raises several questions:

Since it appears that the unaffected parents are heterozygotes, would it be considered unusual that there would be no family history of the disorder? How would they be counseled about risks to future children?

Expert Solution & Answer

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

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Answer 4

Textbook Question

Chapter 22, Problem 1CS

CASE STUDY |An unexpected outcome

A newborn screening program identified a baby with a rare autosomal recessive disorder called arginosuccinate aciduria (AGA), which causes high levels of ammonia to accumulate in the blood. Symptoms usually appear in the first week after birth and can progress to include severe liver damage, developmental delay, and mental retardation. AGA occurs with a frequency of about 1 in 70,000 births. There is no history of this disorder in either the father's or mother's family. This case raises several questions:

Since it appears that the unaffected parents are heterozygotes, would it be considered unusual that there would be no family history of the disorder? How would they be counseled about risks to future children?

Expert Solution & Answer

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

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Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 5

Textbook Question

Answer 6

Textbook Question

Answer 7

Expert Solution & Answer

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

Answer 8

Expert Solution & Answer

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

Answer 9

Expert Solution & Answer

Answer 10

Expert Solution & Answer

Answer 11

Summary Introduction

Case summary:

A baby was identified with an autosomal recessive disorder AGA (Arginosuccinate aciduria) that causes the high levels of ammonia accumulation in the blood. After first week of the birth, symptoms appear that leads into the severe liver damage, developmental delay, and mental retardation.

Characters in the case:

A baby with AGA disorder.

Adequate information:

Accumulation of ammonia in the blood occurs in this disorder. Symptoms include sever liver damage, developmental delay, and mental retardation.

To determine:

The unaffected parents are heterozygous that could be consider as unusual as there were no family history of this disorder. They would have counseled about the risks to future children.

Answer 12

Explanation of Solution

Given information:

AGA (Arginosuccinate aciduria) is a genetic disorder that causes the accumulation of ammonia in the blood. The probability of this disorder is 1 in 70,000 births.

AGA is a heritable disorder that directly affects the nervous system that is caused by the accumulation of the argininosuccinic acid in the blood and also in the urine, while some of the patients are subjected to the accumulation of the ammonia.

Mutation in the ASL gene is responsible for the AGA. AGA follows the pattern of autosomal recessive pattern in which two copies of the gene in each cell got altered. The parents of the person with this disorder are the carriers of one copy of the altered gene and do not show any kind of signs and symptoms of this disorder. This is not unusual as in the history of the family no one was affected by this disorder and this will only happen when two heterozygous individuals meet. The risk of future child to be affected by AGA is of high frequency. There is 25% chances of having affected child with every future child.

Answer 13

Conclusion

Therefore, it can be concluded that the risk associated with each child for this disease is 25%.

Answer 14

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