# 300559

GLYCOGEN STORAGE DISEASE IXd; GSD9D


Alternative titles; symbols

GSD IXd
MUSCLE PHOSPHORYLASE KINASE DEFICIENCY
MUSCLE GLYCOGENOSIS, X-LINKED


Phenotype-Gene Relationships

Location Phenotype Phenotype
MIM number
Inheritance Phenotype
mapping key
Gene/Locus Gene/Locus
MIM number
Xq13.1 Muscle glycogenosis 300559 XLR 3 PHKA1 311870
Clinical Synopsis
 
Phenotypic Series
 

INHERITANCE
- X-linked recessive
MUSCLE, SOFT TISSUES
- Muscle weakness
- Muscle atrophy
- Muscle pain, exercise-induced
- Muscle stiffness, exercise-induced
- Exercise intolerance
- Muscle biopsy shows increased subsarcolemmal vacuolar glycogen accumulation
- Muscle biopsy shows mitochondrial paracrystalline inclusions
- Muscle biopsy shows decreased muscle-specific phosphorylase kinase activity
LABORATORY ABNORMALITIES
- Increased serum creatine kinase
- Myoglobinuria, exercise-induced
MISCELLANEOUS
- Variable age at onset (childhood to adult)
- Most patients have adult onset of symptoms
MOLECULAR BASIS
- Caused by mutation in the muscle-specific phosphorylase kinase subunit A1 gene (PHKA1, 311870.0001)
Glycogen storage disease - PS232200 - 24 Entries
Location Phenotype Inheritance Phenotype
mapping key
Phenotype
MIM number
Gene/Locus Gene/Locus
MIM number
1p31.3 Congenital disorder of glycosylation, type It AR 3 614921 PGM1 171900
1p21.2 Glycogen storage disease IIIb AR 3 232400 AGL 610860
1p21.2 Glycogen storage disease IIIa AR 3 232400 AGL 610860
3p12.2 Glycogen storage disease IV AR 3 232500 GBE1 607839
3q24 ?Glycogen storage disease XV AR 3 613507 GYG1 603942
7p13 Glycogen storage disease X AR 3 261670 PGAM2 612931
7q36.1 Glycogen storage disease of heart, lethal congenital AD 3 261740 PRKAG2 602743
11p15.1 Glycogen storage disease XI AR 3 612933 LDHA 150000
11q13.1 McArdle disease AR 3 232600 PYGM 608455
11q23.3 Glycogen storage disease Ib AR 3 232220 SLC37A4 602671
11q23.3 Glycogen storage disease Ic AR 3 232240 SLC37A4 602671
12p12.1 Glycogen storage disease 0, liver AR 3 240600 GYS2 138571
12q13.11 Glycogen storage disease VII AR 3 232800 PFKM 610681
14q22.1 Glycogen storage disease VI AR 3 232700 PYGL 613741
16p11.2 Glycogen storage disease XII AR 3 611881 ALDOA 103850
16p11.2 Glycogen storage disease IXc AR 3 613027 PHKG2 172471
16q12.1 Phosphorylase kinase deficiency of liver and muscle, autosomal recessive AR 3 261750 PHKB 172490
17p13.2 Glycogen storage disease XIII AR 3 612932 ENO3 131370
17q21.31 Glycogen storage disease Ia AR 3 232200 G6PC 613742
17q25.3 Glycogen storage disease II AR 3 232300 GAA 606800
19q13.33 Glycogen storage disease 0, muscle AR 3 611556 GYS1 138570
Xp22.13 Glycogen storage disease, type IXa1 XLR 3 306000 PHKA2 300798
Xp22.13 Glycogen storage disease, type IXa2 XLR 3 306000 PHKA2 300798
Xq13.1 Muscle glycogenosis XLR 3 300559 PHKA1 311870

TEXT

A number sign (#) is used with this entry because glycogen storage disease IXd (GDS9D), also known as X-linked muscle phosphorylase kinase deficiency, is caused by mutation in the PHKA1 gene (311870), which encodes the alpha subunit of muscle phosphorylase kinase, on chromosome Xq13.


Description

Glycogen storage disease IXd (GSD9D) is an X-linked recessive, relatively mild metabolic disorder characterized by variable exercise-induced muscle weakness or stiffness. Most patients have adult onset of symptoms, and some remain asymptomatic even in late adulthood. The phenotype is usually only apparent with intense exercise (summary by Preisler et al., 2012).

For a discussion of genetic heterogeneity of GSD IX, see GSD9A (306000).


Clinical Features

Abarbanel et al. (1986) reported a 35-year-old man with severe exercise intolerance and muscle cramps. Muscle biopsy showed subsarcolemmal and intermyofibrillar accumulation of glycogen. Muscle phosphorylase kinase activity was 12% of control values.

Clemens et al. (1990) reported 2 unrelated patients with muscle phosphorylase kinase deficiency. Patient 1 was a 58-year-old man who had predominantly distal weakness beginning at age 46 years, but no cramps on exertion. Patient 2 was a 26-year-old man who had had cramps on exertion since age 6, but no muscle weakness. Muscle lactate production during ischemic exercise was impaired only in the first patient. In both patients, serum creatine kinase level was elevated, muscle phosphorylase kinase activity was low, and red cell activity was normal. Liver-specific phosphorylase kinase (300798) activity, measured in patient 1, was also normal. Wehner et al. (1994) provided follow-up on patient 1 reported by Clemens et al. (1990). He had slowly progressive, predominantly distal muscle weakness and atrophy beginning at age 46. He showed symptoms of hypoglycemia upon exertion. At age 64 years, he had weakness of the leg, arm, and abdominal muscles, rapid fatigue on exercise, and requirement for ankle braces. Phosphorylase kinase activity was 0.3% of normal in muscle, but normal in red blood cells and liver. Muscle biopsy showed mild glycogenosis with subsarcolemmal accumulations of glycogen and focal muscle fiber necrosis. The patient's mother, who died at the age of about 26 years, and his daughter, aged 33 at the time of the report, were reportedly asymptomatic. Burwinkel et al. (2003) reported follow-up on patient 2 reported by Clemens et al. (1990). At follow-up, he was a 36-year-old man with exercise-induced cramps, pain, and early fatigue since age 6 years, and occasional pigmenturia after intense exertion. Muscle glycogen concentration was elevated, and subsarcolemmal glycogen accumulation was observed in muscle histology. Total phosphorylase was normal in muscle, and phosphorylase kinase activity was markedly reduced in muscle, but normal in red blood cells.

Wuyts et al. (2005) reported a man with muscle phosphorylase kinase deficiency confirmed by genetic analysis (311870.0004). He first presented at age 43 years with pain and weakness of the quadriceps muscle. Creatine kinase was mildly elevated. Over the subsequent 8 years, he had slowly progressive weakness of the pelvic girdle muscles without pyramidal or cerebellar signs. Muscle biopsy and ultrastructural analysis showed large amounts of subsarcolemmal free glycogen accumulation and a few mitochondrial paracrystalline inclusions. Biochemical analysis showed normal total muscle phosphorylase activity, but absence of phosphorylase kinase activity.

Orngreen et al. (2008) reported a 50-year-old man with muscle phosphorylase kinase deficiency confirmed by genetic analysis (311870.0005). He reported progressive exercise intolerance, muscle stiffness on exercise, and nighttime muscle cramps since childhood. Serum creatine kinase levels were mildly elevated on several occasions, and there was low muscle PHK activity and high muscle glycogen content. During a cycle ergonometry test, the patient showed low-normal maximum oxidative capacity that was higher than that of 12 patients with McArdle disease, or myophosphorylase deficiency (232600). Peak serum lactate of the patient with PHK deficiency was decreased compared to 5 healthy men, but higher than that of the those with McArdle disease, indicating impaired oxidation of carbohydrate in the disease groups. The patient with PHK deficiency showed mild improvement of exercise tolerance with intravenous glucose infusion. There was a normal increase in serum lactate in the forearm ischemic exercise test, suggesting a discrepancy in glycogen breakdown impairment during anaerobic and aerobic exercise in PHK deficiency that may result from different activation pathways for myophosphorylase. Overall, the findings demonstrated that X-linked PHK deficiency is a mild metabolic myopathy characterized by impaired lactate production during moderate-intensity dynamic exercise and mild elevations of plasma creatine kinase and muscle glycogen content. Orngreen et al. (2008) noted that the clinical severity of PHK deficiency resembles another partial glycolytic defect, phosphoglycerate mutase deficiency (261670).

Preisler et al. (2012) reported 2 unrelated adult men with genetically confirmed GSD IXd: a 39-year-old with mild exercise-induced forearm pain and a 69-year-old with persistently increased serum creatine kinase after statin treatment (see 311870.0004), but no other symptoms. Both patients had increased glycogen levels in muscle and PHK activity less than 11% of normal. Both had a normal increase in plasma lactate on anaerobic exercise, but showed an exaggerated 5-fold increase in ammonia levels. An incremental exercise test revealed a blunted lactate response compared to controls; fat and carbohydrate oxidation rates at 70% of peak oxygen consumption were normal. Glucose infusion did not improve work capacity. Preisler et al. (2012) concluded that muscle PHK deficiency may present as an almost asymptomatic condition, despite a mild impairment of muscle glycogenolysis, raised CK levels, and glycogen accumulation in muscle. The relative preservation of glycogenolysis was explained by activation of myophosphorylase (PYGM; 608455) at high exercise intensities.


Molecular Genetics

In patient 1 with phosphorylase kinase deficiency reported by Clemens et al. (1990), Wehner et al. (1994) identified a nonsense mutation in the PHKA1 gene (311870.0001). The findings confirmed that the condition in this patient was a human homolog of the X-linked muscle Phk deficiency of the I-strain mouse (Schneider et al., 1993). In patient 2 of Clemens et al. (1990), Burwinkel et al. (2003) identified a missense mutation in the PHKA1 gene (311870.0003).

Burwinkel et al. (2003) screened 5 other patients with decreased muscle PHK activity for mutations in 6 genes that contribute to muscle PHK, in the muscle isoform of glycogen phosphorylase (PYGM; 608455), and in a muscle-specific regulatory subunit of protein kinase (PRKAG3; 604976). Two patients were heterozygous for single amino acid replacements of unclear significance in the beta subunit of phosphorylase kinase (PHKB; 172490).

Bruno et al. (1998) reported a splice junction mutation in the PHKA1 gene (311870.0002) in a 28-year old Caucasian male with exercise intolerance, myoglobinuria, and muscle phosphorylase kinase deficiency. The patient, reported as patient 1 of Wilkinson et al. (1994), had been diagnosed with PHK deficiency at age 15 years.


REFERENCES

  1. Abarbanel, J. M., Bashan, N., Potashnik, R., Osimani, A., Moses, S. W., Herishanu, Y. Adult muscle phosphorylase 'b' kinase deficiency. Neurology 36: 560-562, 1986. [PubMed: 3083284, related citations] [Full Text]

  2. Bruno, C., Manfredi, G., Andreu, A. L., Shanske, S., Krishna, S., Ilse, W. K., DiMauro, S. A splice junction mutation in the alpha-M gene of phosphorylase kinase in a patient with myopathy. Biochem. Biophys. Res. Commun. 249: 648-651, 1998. [PubMed: 9731190, related citations] [Full Text]

  3. Burwinkel, B., Hu, B., Schroers, A., Clemens, P. R., Moses, S. W., Shin, Y. S., Pongratz, D., Vorgerd, M., Kilimann, M. W. Muscle glycogenosis with low phosphorylase kinase activity: mutations in PHKA1, PHKG1 or six other candidate genes explain only a minority of cases. Europ. J. Hum. Genet. 11: 516-526, 2003. [PubMed: 12825073, related citations] [Full Text]

  4. Clemens, P. R., Yamamoto, M., Engel, A. G. Adult phosphorylase b kinase deficiency. Ann. Neurol. 28: 529-538, 1990. [PubMed: 2252364, related citations] [Full Text]

  5. Orngreen, M. C., Schelhaas, H. J., Jeppesen, T. D., Akman, H. O., Wevers, R. A., Andersen, S. T., ter Laak, H. J., van Diggelen, O. P., DiMauro, S., Vissing, J. Is muscle glycogenolysis impaired in X-linked phosphorylase b kinase deficiency? Neurology 70: 1876-1882, 2008. [PubMed: 18401027, related citations] [Full Text]

  6. Preisler, N., Orngreen, M. C., Echaniz-Laguna, A., Laforet, P., Lonsdorfer-Wolf, E., Doutreleau, S., Geny, B., Akman, H.O., DiMauro, S., Vissing, J. Muscle phosphorylase kinase deficiency: a neutral metabolic variant or a disease? Neurology 78: 265-268, 2012. [PubMed: 22238410, related citations] [Full Text]

  7. Schneider, A., Davidson, J. J., Wullrich, A., Kilimann, M. W. Phosphorylase kinase deficiency in I-strain mice is associated with a frameshift mutation in the alpha-subunit muscle isoform. Nature Genet. 5: 381-385, 1993. [PubMed: 8298647, related citations] [Full Text]

  8. Wehner, M., Clemens, P. R., Engel, A. G., Kilimann, M. W. Human muscle glycogenosis due to phosphorylase kinase deficiency associated with a nonsense mutation in the muscle isoform of the alpha subunit. Hum. Molec. Genet. 3: 1983-1987, 1994. [PubMed: 7874115, related citations] [Full Text]

  9. Wilkinson, D. A., Tonin, P., Shanske, S., Lombes, A., Carlson, G. M., DiMauro, S. Clinical and biochemical features of 10 adult patients with muscle phosphorylase kinase deficiency. Neurology 44: 461-466, 1994. [PubMed: 8145916, related citations] [Full Text]

  10. Wuyts, W., Reyniers, E., Ceuterick, C., Storm, K., de Barsy, T., Martin, J.-J. Myopathy and phosphorylase kinase deficiency caused by a mutation in the PHKA1 gene. Am. J. Med. Genet. 133A: 82-84, 2005. [PubMed: 15637709, related citations] [Full Text]


Cassandra L. Kniffin - updated : 10/31/2012
Cassandra L. Kniffin - updated : 9/30/2008
Creation Date:
Cassandra L. Kniffin : 10/12/2005
carol : 05/11/2022
carol : 07/15/2021
carol : 06/20/2019
alopez : 09/23/2016
mcolton : 05/01/2014
carol : 11/6/2012
ckniffin : 10/31/2012
carol : 12/1/2010
carol : 10/1/2009
ckniffin : 9/24/2009
wwang : 10/3/2008
ckniffin : 9/30/2008
carol : 4/17/2007
carol : 10/19/2005
ckniffin : 10/12/2005

# 300559

GLYCOGEN STORAGE DISEASE IXd; GSD9D


Alternative titles; symbols

GSD IXd
MUSCLE PHOSPHORYLASE KINASE DEFICIENCY
MUSCLE GLYCOGENOSIS, X-LINKED


SNOMEDCT: 819953000;   ORPHA: 715;   DO: 0111040;  


Phenotype-Gene Relationships

Location Phenotype Phenotype
MIM number
Inheritance Phenotype
mapping key
Gene/Locus Gene/Locus
MIM number
Xq13.1 Muscle glycogenosis 300559 X-linked recessive 3 PHKA1 311870

TEXT

A number sign (#) is used with this entry because glycogen storage disease IXd (GDS9D), also known as X-linked muscle phosphorylase kinase deficiency, is caused by mutation in the PHKA1 gene (311870), which encodes the alpha subunit of muscle phosphorylase kinase, on chromosome Xq13.


Description

Glycogen storage disease IXd (GSD9D) is an X-linked recessive, relatively mild metabolic disorder characterized by variable exercise-induced muscle weakness or stiffness. Most patients have adult onset of symptoms, and some remain asymptomatic even in late adulthood. The phenotype is usually only apparent with intense exercise (summary by Preisler et al., 2012).

For a discussion of genetic heterogeneity of GSD IX, see GSD9A (306000).


Clinical Features

Abarbanel et al. (1986) reported a 35-year-old man with severe exercise intolerance and muscle cramps. Muscle biopsy showed subsarcolemmal and intermyofibrillar accumulation of glycogen. Muscle phosphorylase kinase activity was 12% of control values.

Clemens et al. (1990) reported 2 unrelated patients with muscle phosphorylase kinase deficiency. Patient 1 was a 58-year-old man who had predominantly distal weakness beginning at age 46 years, but no cramps on exertion. Patient 2 was a 26-year-old man who had had cramps on exertion since age 6, but no muscle weakness. Muscle lactate production during ischemic exercise was impaired only in the first patient. In both patients, serum creatine kinase level was elevated, muscle phosphorylase kinase activity was low, and red cell activity was normal. Liver-specific phosphorylase kinase (300798) activity, measured in patient 1, was also normal. Wehner et al. (1994) provided follow-up on patient 1 reported by Clemens et al. (1990). He had slowly progressive, predominantly distal muscle weakness and atrophy beginning at age 46. He showed symptoms of hypoglycemia upon exertion. At age 64 years, he had weakness of the leg, arm, and abdominal muscles, rapid fatigue on exercise, and requirement for ankle braces. Phosphorylase kinase activity was 0.3% of normal in muscle, but normal in red blood cells and liver. Muscle biopsy showed mild glycogenosis with subsarcolemmal accumulations of glycogen and focal muscle fiber necrosis. The patient's mother, who died at the age of about 26 years, and his daughter, aged 33 at the time of the report, were reportedly asymptomatic. Burwinkel et al. (2003) reported follow-up on patient 2 reported by Clemens et al. (1990). At follow-up, he was a 36-year-old man with exercise-induced cramps, pain, and early fatigue since age 6 years, and occasional pigmenturia after intense exertion. Muscle glycogen concentration was elevated, and subsarcolemmal glycogen accumulation was observed in muscle histology. Total phosphorylase was normal in muscle, and phosphorylase kinase activity was markedly reduced in muscle, but normal in red blood cells.

Wuyts et al. (2005) reported a man with muscle phosphorylase kinase deficiency confirmed by genetic analysis (311870.0004). He first presented at age 43 years with pain and weakness of the quadriceps muscle. Creatine kinase was mildly elevated. Over the subsequent 8 years, he had slowly progressive weakness of the pelvic girdle muscles without pyramidal or cerebellar signs. Muscle biopsy and ultrastructural analysis showed large amounts of subsarcolemmal free glycogen accumulation and a few mitochondrial paracrystalline inclusions. Biochemical analysis showed normal total muscle phosphorylase activity, but absence of phosphorylase kinase activity.

Orngreen et al. (2008) reported a 50-year-old man with muscle phosphorylase kinase deficiency confirmed by genetic analysis (311870.0005). He reported progressive exercise intolerance, muscle stiffness on exercise, and nighttime muscle cramps since childhood. Serum creatine kinase levels were mildly elevated on several occasions, and there was low muscle PHK activity and high muscle glycogen content. During a cycle ergonometry test, the patient showed low-normal maximum oxidative capacity that was higher than that of 12 patients with McArdle disease, or myophosphorylase deficiency (232600). Peak serum lactate of the patient with PHK deficiency was decreased compared to 5 healthy men, but higher than that of the those with McArdle disease, indicating impaired oxidation of carbohydrate in the disease groups. The patient with PHK deficiency showed mild improvement of exercise tolerance with intravenous glucose infusion. There was a normal increase in serum lactate in the forearm ischemic exercise test, suggesting a discrepancy in glycogen breakdown impairment during anaerobic and aerobic exercise in PHK deficiency that may result from different activation pathways for myophosphorylase. Overall, the findings demonstrated that X-linked PHK deficiency is a mild metabolic myopathy characterized by impaired lactate production during moderate-intensity dynamic exercise and mild elevations of plasma creatine kinase and muscle glycogen content. Orngreen et al. (2008) noted that the clinical severity of PHK deficiency resembles another partial glycolytic defect, phosphoglycerate mutase deficiency (261670).

Preisler et al. (2012) reported 2 unrelated adult men with genetically confirmed GSD IXd: a 39-year-old with mild exercise-induced forearm pain and a 69-year-old with persistently increased serum creatine kinase after statin treatment (see 311870.0004), but no other symptoms. Both patients had increased glycogen levels in muscle and PHK activity less than 11% of normal. Both had a normal increase in plasma lactate on anaerobic exercise, but showed an exaggerated 5-fold increase in ammonia levels. An incremental exercise test revealed a blunted lactate response compared to controls; fat and carbohydrate oxidation rates at 70% of peak oxygen consumption were normal. Glucose infusion did not improve work capacity. Preisler et al. (2012) concluded that muscle PHK deficiency may present as an almost asymptomatic condition, despite a mild impairment of muscle glycogenolysis, raised CK levels, and glycogen accumulation in muscle. The relative preservation of glycogenolysis was explained by activation of myophosphorylase (PYGM; 608455) at high exercise intensities.


Molecular Genetics

In patient 1 with phosphorylase kinase deficiency reported by Clemens et al. (1990), Wehner et al. (1994) identified a nonsense mutation in the PHKA1 gene (311870.0001). The findings confirmed that the condition in this patient was a human homolog of the X-linked muscle Phk deficiency of the I-strain mouse (Schneider et al., 1993). In patient 2 of Clemens et al. (1990), Burwinkel et al. (2003) identified a missense mutation in the PHKA1 gene (311870.0003).

Burwinkel et al. (2003) screened 5 other patients with decreased muscle PHK activity for mutations in 6 genes that contribute to muscle PHK, in the muscle isoform of glycogen phosphorylase (PYGM; 608455), and in a muscle-specific regulatory subunit of protein kinase (PRKAG3; 604976). Two patients were heterozygous for single amino acid replacements of unclear significance in the beta subunit of phosphorylase kinase (PHKB; 172490).

Bruno et al. (1998) reported a splice junction mutation in the PHKA1 gene (311870.0002) in a 28-year old Caucasian male with exercise intolerance, myoglobinuria, and muscle phosphorylase kinase deficiency. The patient, reported as patient 1 of Wilkinson et al. (1994), had been diagnosed with PHK deficiency at age 15 years.


REFERENCES

  1. Abarbanel, J. M., Bashan, N., Potashnik, R., Osimani, A., Moses, S. W., Herishanu, Y. Adult muscle phosphorylase 'b' kinase deficiency. Neurology 36: 560-562, 1986. [PubMed: 3083284] [Full Text: https://doi.org/10.1212/wnl.36.4.560]

  2. Bruno, C., Manfredi, G., Andreu, A. L., Shanske, S., Krishna, S., Ilse, W. K., DiMauro, S. A splice junction mutation in the alpha-M gene of phosphorylase kinase in a patient with myopathy. Biochem. Biophys. Res. Commun. 249: 648-651, 1998. [PubMed: 9731190] [Full Text: https://doi.org/10.1006/bbrc.1998.9211]

  3. Burwinkel, B., Hu, B., Schroers, A., Clemens, P. R., Moses, S. W., Shin, Y. S., Pongratz, D., Vorgerd, M., Kilimann, M. W. Muscle glycogenosis with low phosphorylase kinase activity: mutations in PHKA1, PHKG1 or six other candidate genes explain only a minority of cases. Europ. J. Hum. Genet. 11: 516-526, 2003. [PubMed: 12825073] [Full Text: https://doi.org/10.1038/sj.ejhg.5200996]

  4. Clemens, P. R., Yamamoto, M., Engel, A. G. Adult phosphorylase b kinase deficiency. Ann. Neurol. 28: 529-538, 1990. [PubMed: 2252364] [Full Text: https://doi.org/10.1002/ana.410280410]

  5. Orngreen, M. C., Schelhaas, H. J., Jeppesen, T. D., Akman, H. O., Wevers, R. A., Andersen, S. T., ter Laak, H. J., van Diggelen, O. P., DiMauro, S., Vissing, J. Is muscle glycogenolysis impaired in X-linked phosphorylase b kinase deficiency? Neurology 70: 1876-1882, 2008. [PubMed: 18401027] [Full Text: https://doi.org/10.1212/01.wnl.0000289190.66955.67]

  6. Preisler, N., Orngreen, M. C., Echaniz-Laguna, A., Laforet, P., Lonsdorfer-Wolf, E., Doutreleau, S., Geny, B., Akman, H.O., DiMauro, S., Vissing, J. Muscle phosphorylase kinase deficiency: a neutral metabolic variant or a disease? Neurology 78: 265-268, 2012. [PubMed: 22238410] [Full Text: https://doi.org/10.1212/WNL.0b013e31824365f9]

  7. Schneider, A., Davidson, J. J., Wullrich, A., Kilimann, M. W. Phosphorylase kinase deficiency in I-strain mice is associated with a frameshift mutation in the alpha-subunit muscle isoform. Nature Genet. 5: 381-385, 1993. [PubMed: 8298647] [Full Text: https://doi.org/10.1038/ng1293-381]

  8. Wehner, M., Clemens, P. R., Engel, A. G., Kilimann, M. W. Human muscle glycogenosis due to phosphorylase kinase deficiency associated with a nonsense mutation in the muscle isoform of the alpha subunit. Hum. Molec. Genet. 3: 1983-1987, 1994. [PubMed: 7874115] [Full Text: https://doi.org/10.1093/hmg/3.11.1983]

  9. Wilkinson, D. A., Tonin, P., Shanske, S., Lombes, A., Carlson, G. M., DiMauro, S. Clinical and biochemical features of 10 adult patients with muscle phosphorylase kinase deficiency. Neurology 44: 461-466, 1994. [PubMed: 8145916] [Full Text: https://doi.org/10.1212/wnl.44.3_part_1.461]

  10. Wuyts, W., Reyniers, E., Ceuterick, C., Storm, K., de Barsy, T., Martin, J.-J. Myopathy and phosphorylase kinase deficiency caused by a mutation in the PHKA1 gene. Am. J. Med. Genet. 133A: 82-84, 2005. [PubMed: 15637709] [Full Text: https://doi.org/10.1002/ajmg.a.30517]


Contributors:
Cassandra L. Kniffin - updated : 10/31/2012
Cassandra L. Kniffin - updated : 9/30/2008

Creation Date:
Cassandra L. Kniffin : 10/12/2005

Edit History:
carol : 05/11/2022
carol : 07/15/2021
carol : 06/20/2019
alopez : 09/23/2016
mcolton : 05/01/2014
carol : 11/6/2012
ckniffin : 10/31/2012
carol : 12/1/2010
carol : 10/1/2009
ckniffin : 9/24/2009
wwang : 10/3/2008
ckniffin : 9/30/2008
carol : 4/17/2007
carol : 10/19/2005
ckniffin : 10/12/2005