Genetic Pathways, Part 1

Review the PDF of the fact sheet on genetic pathways,

with board-relevant, easy-to-review material. This fact sheet details some of the important pathways in dermatology and the clinical manifestations seen with these genetic derangements.

After, test your knowledge by answering the 5 practice questions.

Practice Questions

1. Which keratinization disorder is characterized by drastically lower levels of lamellar bodies?

a. Harlequin ichthyosis

b. ichthyosis vulgaris

c. lamellar ichthyosis

d. nonbullous congenital ichthyosiform erythroderma

e. X-linked ichthyosis

 

2. Mutation of this enzyme leads to uncontrolled proteolytic activity causing degradation of lamellar body lipid processing enzymes.

a. FALDH (fatty aldehyde dehydrogenase)

b. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

c. PEX7 (perioxsomal biogenesis factor 7)

d. PHYH (phytanoyl-CoA hydroxylase)

e. NSDHL (NAD[P] dependent steroid dehydrogenase-like)

 

3. A 30-year-old man presented for evaluation of abnormal nails. Physical examination revealed a red streak with distal V-shaped nicking. Numerous keratotic papules on the hands and chest and oral papules also were noted. The gene responsible for these findings encodes a Ca²⁺-ATPase responsible for a Ca²⁺ influx into what cellular structure?

a. cytoplasm

b. endoplasmic reticulum

c. golgi

d. nucleus

e. ribosome

 

4. A female neonate aged 2 weeks presented with linear and whorled vesicles on the thighs and trunk. The delivery was uncomplicated. The patient was afebrile, but her mother said she has been “doing well” at home. On pathology, what do you expect to see?

a. apoptosis of epidermal cells

b. cell-poor blister

c. molding and margination of chromatin as well as multinucleated giant cells

d. numerous pseudohyphae

e. spongiosis of epidermal cells

 

5. A young child presents with linear atrophic plaques with fat herniation and raspberrylike oral papillomas. What signal transduction pathway is altered in this syndrome?

a. ABCA12 (ATP-binding cassette, sub-family A, member 12)

b. adenylate cyclase

c. ß-catenin

d. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

e. nuclear factor κ light chain enhancer of activated B cells

The answers appear on the next page.

 

Practice Question Answers

1. Which keratinization disorder is characterized by drastically lower levels of lamellar bodies?

a. Harlequin ichthyosis

b. ichthyosis vulgaris

c. lamellar ichthyosis

d. nonbullous congenital ichthyosiform erythroderma

e. X-linked ichthyosis

 

2. Mutation of this enzyme leads to uncontrolled proteolytic activity causing degradation of lamellar body lipid processing enzymes.

a. FALDH (fatty aldehyde dehydrogenase)

b. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

c. PEX7 (perioxsomal biogenesis factor 7)

d. PHYH (phytanoyl-CoA hydroxylase)

e. NSDHL (NAD[P] dependent steroid dehydrogenase-like)

 

3. A 30-year-old man presented for evaluation of abnormal nails. Physical examination revealed a red streak with distal V-shaped nicking. Numerous keratotic papules on the hands and chest and oral papules also were noted. The gene responsible for these findings encodes a Ca²⁺-ATPase responsible for a Ca²⁺ influx into what cellular structure?

a. cytoplasm

b. endoplasmic reticulum

c. golgi

d. nucleus

e. ribosome

 

4. A female neonate aged 2 weeks presented with linear and whorled vesicles on the thighs and trunk. The delivery was uncomplicated. The patient was afebrile, but her mother said she has been “doing well” at home. On pathology, what do you expect to see?

a. apoptosis of epidermal cells

b. cell-poor blister

c. molding and margination of chromatin as well as multinucleated giant cells

d. numerous pseudohyphae

e. spongiosis of epidermal cells

 

5. A young child presents with linear atrophic plaques with fat herniation and raspberrylike oral papillomas. What signal transduction pathway is altered in this syndrome?

a. ABCA12 (ATP-binding cassette, sub-family A, member 12)

b. adenylate cyclase

c. ß-catenin

d. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

e. nuclear factor κ light chain enhancer of activated B cells

Review the PDF of the fact sheet on genetic pathways,

with board-relevant, easy-to-review material. This fact sheet details some of the important pathways in dermatology and the clinical manifestations seen with these genetic derangements.

After, test your knowledge by answering the 5 practice questions.

Practice Questions

1. Which keratinization disorder is characterized by drastically lower levels of lamellar bodies?

a. Harlequin ichthyosis

b. ichthyosis vulgaris

c. lamellar ichthyosis

d. nonbullous congenital ichthyosiform erythroderma

e. X-linked ichthyosis

 

2. Mutation of this enzyme leads to uncontrolled proteolytic activity causing degradation of lamellar body lipid processing enzymes.

a. FALDH (fatty aldehyde dehydrogenase)

b. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

c. PEX7 (perioxsomal biogenesis factor 7)

d. PHYH (phytanoyl-CoA hydroxylase)

e. NSDHL (NAD[P] dependent steroid dehydrogenase-like)

 

3. A 30-year-old man presented for evaluation of abnormal nails. Physical examination revealed a red streak with distal V-shaped nicking. Numerous keratotic papules on the hands and chest and oral papules also were noted. The gene responsible for these findings encodes a Ca²⁺-ATPase responsible for a Ca²⁺ influx into what cellular structure?

a. cytoplasm

b. endoplasmic reticulum

c. golgi

d. nucleus

e. ribosome

 

4. A female neonate aged 2 weeks presented with linear and whorled vesicles on the thighs and trunk. The delivery was uncomplicated. The patient was afebrile, but her mother said she has been “doing well” at home. On pathology, what do you expect to see?

a. apoptosis of epidermal cells

b. cell-poor blister

c. molding and margination of chromatin as well as multinucleated giant cells

d. numerous pseudohyphae

e. spongiosis of epidermal cells

 

5. A young child presents with linear atrophic plaques with fat herniation and raspberrylike oral papillomas. What signal transduction pathway is altered in this syndrome?

a. ABCA12 (ATP-binding cassette, sub-family A, member 12)

b. adenylate cyclase

c. ß-catenin

d. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

e. nuclear factor κ light chain enhancer of activated B cells

The answers appear on the next page.

 

Practice Question Answers

1. Which keratinization disorder is characterized by drastically lower levels of lamellar bodies?

a. Harlequin ichthyosis

b. ichthyosis vulgaris

c. lamellar ichthyosis

d. nonbullous congenital ichthyosiform erythroderma

e. X-linked ichthyosis

 

2. Mutation of this enzyme leads to uncontrolled proteolytic activity causing degradation of lamellar body lipid processing enzymes.

a. FALDH (fatty aldehyde dehydrogenase)

b. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

c. PEX7 (perioxsomal biogenesis factor 7)

d. PHYH (phytanoyl-CoA hydroxylase)

e. NSDHL (NAD[P] dependent steroid dehydrogenase-like)

 

3. A 30-year-old man presented for evaluation of abnormal nails. Physical examination revealed a red streak with distal V-shaped nicking. Numerous keratotic papules on the hands and chest and oral papules also were noted. The gene responsible for these findings encodes a Ca²⁺-ATPase responsible for a Ca²⁺ influx into what cellular structure?

a. cytoplasm

b. endoplasmic reticulum

c. golgi

d. nucleus

e. ribosome

 

4. A female neonate aged 2 weeks presented with linear and whorled vesicles on the thighs and trunk. The delivery was uncomplicated. The patient was afebrile, but her mother said she has been “doing well” at home. On pathology, what do you expect to see?

a. apoptosis of epidermal cells

b. cell-poor blister

c. molding and margination of chromatin as well as multinucleated giant cells

d. numerous pseudohyphae

e. spongiosis of epidermal cells

 

5. A young child presents with linear atrophic plaques with fat herniation and raspberrylike oral papillomas. What signal transduction pathway is altered in this syndrome?

a. ABCA12 (ATP-binding cassette, sub-family A, member 12)

b. adenylate cyclase

c. ß-catenin

d. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

e. nuclear factor κ light chain enhancer of activated B cells

Review the PDF of the fact sheet on genetic pathways,

with board-relevant, easy-to-review material. This fact sheet details some of the important pathways in dermatology and the clinical manifestations seen with these genetic derangements.

After, test your knowledge by answering the 5 practice questions.

Practice Questions

1. Which keratinization disorder is characterized by drastically lower levels of lamellar bodies?

a. Harlequin ichthyosis

b. ichthyosis vulgaris

c. lamellar ichthyosis

d. nonbullous congenital ichthyosiform erythroderma

e. X-linked ichthyosis

 

2. Mutation of this enzyme leads to uncontrolled proteolytic activity causing degradation of lamellar body lipid processing enzymes.

a. FALDH (fatty aldehyde dehydrogenase)

b. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

c. PEX7 (perioxsomal biogenesis factor 7)

d. PHYH (phytanoyl-CoA hydroxylase)

e. NSDHL (NAD[P] dependent steroid dehydrogenase-like)

 

3. A 30-year-old man presented for evaluation of abnormal nails. Physical examination revealed a red streak with distal V-shaped nicking. Numerous keratotic papules on the hands and chest and oral papules also were noted. The gene responsible for these findings encodes a Ca²⁺-ATPase responsible for a Ca²⁺ influx into what cellular structure?

a. cytoplasm

b. endoplasmic reticulum

c. golgi

d. nucleus

e. ribosome

 

4. A female neonate aged 2 weeks presented with linear and whorled vesicles on the thighs and trunk. The delivery was uncomplicated. The patient was afebrile, but her mother said she has been “doing well” at home. On pathology, what do you expect to see?

a. apoptosis of epidermal cells

b. cell-poor blister

c. molding and margination of chromatin as well as multinucleated giant cells

d. numerous pseudohyphae

e. spongiosis of epidermal cells

 

5. A young child presents with linear atrophic plaques with fat herniation and raspberrylike oral papillomas. What signal transduction pathway is altered in this syndrome?

a. ABCA12 (ATP-binding cassette, sub-family A, member 12)

b. adenylate cyclase

c. ß-catenin

d. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

e. nuclear factor κ light chain enhancer of activated B cells

The answers appear on the next page.

 

Practice Question Answers

1. Which keratinization disorder is characterized by drastically lower levels of lamellar bodies?

a. Harlequin ichthyosis

b. ichthyosis vulgaris

c. lamellar ichthyosis

d. nonbullous congenital ichthyosiform erythroderma

e. X-linked ichthyosis

 

2. Mutation of this enzyme leads to uncontrolled proteolytic activity causing degradation of lamellar body lipid processing enzymes.

a. FALDH (fatty aldehyde dehydrogenase)

b. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

c. PEX7 (perioxsomal biogenesis factor 7)

d. PHYH (phytanoyl-CoA hydroxylase)

e. NSDHL (NAD[P] dependent steroid dehydrogenase-like)

 

3. A 30-year-old man presented for evaluation of abnormal nails. Physical examination revealed a red streak with distal V-shaped nicking. Numerous keratotic papules on the hands and chest and oral papules also were noted. The gene responsible for these findings encodes a Ca²⁺-ATPase responsible for a Ca²⁺ influx into what cellular structure?

a. cytoplasm

b. endoplasmic reticulum

c. golgi

d. nucleus

e. ribosome

 

4. A female neonate aged 2 weeks presented with linear and whorled vesicles on the thighs and trunk. The delivery was uncomplicated. The patient was afebrile, but her mother said she has been “doing well” at home. On pathology, what do you expect to see?

a. apoptosis of epidermal cells

b. cell-poor blister

c. molding and margination of chromatin as well as multinucleated giant cells

d. numerous pseudohyphae

e. spongiosis of epidermal cells

 

5. A young child presents with linear atrophic plaques with fat herniation and raspberrylike oral papillomas. What signal transduction pathway is altered in this syndrome?

a. ABCA12 (ATP-binding cassette, sub-family A, member 12)

b. adenylate cyclase

c. ß-catenin

d. LEKTI (lympho-epithelial Kazal-type-related inhibitor)

e. nuclear factor κ light chain enhancer of activated B cells