Medical Disease Genetics
HUMAN DISEASE GENETICS
Contents
Section 1 Title: The Genes of Osteogenesis Imperfecta 3
Section 2 Title: Pathogenesis of Myotonic Dystrophy Type 1 and Type 2 6
Section 3 Title: Huntington Disease Genetics 8
Section 4 Title: The major forms of Glycogen Storage Disease types I, III and IX 11
Section 1 Title: The Genes of Osteogenesis Imperfecta (word count = 568)
Osteogenesis Imperfecta (OI) is caused by different genes; COL1A1, COL1A2, CRTAP and LEPRE1. Each gene giving rise to a particular phenotype. OI is characterised by tendency to fracture due to brittle bones, bone curvature and short stature.
Osteogenesis Imperfecta has a birth prevalence of 6-7 per 100, 000 persons but each type has a different prevalence and incidence. 85-90% of OI type one cases are caused by mutations in COL1A1/A2 (Martin and Shapiro, 2007). OI occurs equally in males, females and all ethnic groups. The prevalence and incidence of OI types 1-3 in Australian populations can be seen in Table 1 below.
Table 1. Prevalence and incidence of OI types I, II and II. Adopted from Van Dijk et al, (2011).
-------------------------------------------------
Osteogenesis Imperfecta Gene/locus Location Chrm* Prevalence+ Incidence++
-------------------------------------------------
Type 1 (I) COL1A1 17q21.33 3-4/100,000 1-2/100,000
-------------------------------------------------
Type 2 (II) COL1A1 17q21.33 † 1-2/100,000
-------------------------------------------------
COL1A2 7q21.3
-------------------------------------------------
Type 3 (III) COL1A1 17q21.33 1-2/100,000 1.6/100,000
-------------------------------------------------
COL1A2 7q21.3
-------------------------------------------------
Footnotes
-------------------------------------------------
* Location of the gene on the chromosome
-------------------------------------------------
Contents
Section 1 Title: The Genes of Osteogenesis Imperfecta 3
Section 2 Title: Pathogenesis of Myotonic Dystrophy Type 1 and Type 2 6
Section 3 Title: Huntington Disease Genetics 8
Section 4 Title: The major forms of Glycogen Storage Disease types I, III and IX 11
Section 1 Title: The Genes of Osteogenesis Imperfecta (word count = 568)
Osteogenesis Imperfecta (OI) is caused by different genes; COL1A1, COL1A2, CRTAP and LEPRE1. Each gene giving rise to a particular phenotype. OI is characterised by tendency to fracture due to brittle bones, bone curvature and short stature.
Osteogenesis Imperfecta has a birth prevalence of 6-7 per 100, 000 persons but each type has a different prevalence and incidence. 85-90% of OI type one cases are caused by mutations in COL1A1/A2 (Martin and Shapiro, 2007). OI occurs equally in males, females and all ethnic groups. The prevalence and incidence of OI types 1-3 in Australian populations can be seen in Table 1 below.
Table 1. Prevalence and incidence of OI types I, II and II. Adopted from Van Dijk et al, (2011).
-------------------------------------------------
Osteogenesis Imperfecta Gene/locus Location Chrm* Prevalence+ Incidence++
-------------------------------------------------
Type 1 (I) COL1A1 17q21.33 3-4/100,000 1-2/100,000
-------------------------------------------------
Type 2 (II) COL1A1 17q21.33 † 1-2/100,000
-------------------------------------------------
COL1A2 7q21.3
-------------------------------------------------
Type 3 (III) COL1A1 17q21.33 1-2/100,000 1.6/100,000
-------------------------------------------------
COL1A2 7q21.3
-------------------------------------------------
Footnotes
-------------------------------------------------
* Location of the gene on the chromosome
-------------------------------------------------
References: 1. Aoyama, Y., Ozer, I., Demirkol, M., Ebara, T., Murase, T., Podskarbi, T., Shin, Y.S., Gokcay, G., Okubo, M. (2009). Molecular features of 23 patients with glycogen storage disease type III in Turkey: a novel mutation p.R1147G associated with isolated glucosidase deficiency, along with 9 AGL mutations. J. Hum. Genet. 54(11):681-686. This paper looks at genetic mechanisms behind the type III form of the disease. 2. Chou, J.Y. and Mansfield, B.C. (1999). Molecular Genetics of Type 1 Glycogen Storage Diseases. TEM. 10(3): 104-113. This paper is useful and interesting in that it goes into depth on Type 1 GSD. 3. Hasan Özen. (2007). Glycogen storage diseases: New perspectives. World J Gastroenterol. 13(18): 2541-2553. This paper is a general review of the many types of GSD and important for genetic linkage and epidemiology.