X chromosome inactivation in clinical practice

Human Genetics

Volumn 126, Issue 3, 2009, Pages 363-373

  Ørstavik, Karen Helene ^a  

^a OSLO UNIVERSITY HOSPITAL   (Norway)

Author keywords

[No Author keywords available]

Indexed keywords

ANDROGEN RECEPTOR;

ANEUPLOIDY; CHROMOSOME ANALYSIS; CHROMOSOME TRANSLOCATION; CLINICAL PRACTICE; DISEASE CARRIER; DNA DETERMINATION; DNA METHYLATION; GENE EXPRESSION; GENE MUTATION; GENE SILENCING; GENETIC HETEROGENEITY; GENETIC VARIABILITY; HUMAN; HYPER IGM SYNDROME; MENTAL DEFICIENCY; MONOZYGOTIC TWINS; MOSAICISM; PHENOTYPE; PRIORITY JOURNAL; REVIEW; SEX DIFFERENCE; X CHROMOSOME; X CHROMOSOME INACTIVATION; X CHROMOSOME LINKED DISORDER;

ADOLESCENT; ADULT; AGED, 80 AND OVER; CHILD; CHILD, PRESCHOOL; CHROMOSOMES, HUMAN, X; FEMALE; GENE SILENCING; GENETIC DISEASES, X-LINKED; HUMANS; INFANT; INFANT, NEWBORN; MALE; PHENOTYPE; X CHROMOSOME INACTIVATION;

MAMMALIA;

EID: 70349314767     PISSN: 03406717     EISSN: 14321203     Source Type: Journal    
DOI: 10.1007/s00439-009-0670-5     Document Type: Review

References (112)

1. Allen RC, Zoghbi HY, Moseley AB, Rosenblatt HM, Belmont JW (1992) Methylation of HpaII and HhaI sites near the polymorphic CAG repeat in the human androgen-receptor gene correlates with X chromosome inactivation. Am J Hum Genet 51:1229-1239
2. Amos-Landgraf JM, Cottle A, Plenge RM, Friez M, Schwartz CE, Longshore J, Willard HF (2006) X chromosome-inactivation patterns of 1, 005 phenotypically unaffected females. Am J Hum Genet 79:493-499
3. Andreu N, Pujol-Moix N, Martinez-Lostao L, Oset M, Muñiz-Diaz E, Estivill X, Volpini V, Fillat C (2003) Wiskott-Aldrich syndrome in a female with skewed X-chromosome inactivation. Blood Cells Mol Dis 31:332-337
4. Archer H, Evans J, Leonard H, Colvin L, Ravine D, Christodoulou J, Williamson S, Charman T, Bailey ME, Sampson J, de Klerk N, Clarke A (2007) Correlation between clinical severity in patients with Rett syndrome with a p.R168X or p.T158M MECP2 mutation, and the direction and degree of skewing of X-chromosome inactivation. J Med Genet 44:148-152
5. Au WY, Ma ES, Lam VM, Chan JL, Pang A, Kwong YL (2004) Glucose 6-phosphate dehydrogenase (G6PD) deficiency in elderly Chinese women heterozygous for G6PD variants. Am J Med Genet 129:208-211
6. Au WY, Lam V, Pang A, Lee WM, Chan JL, Song YQ, Ma ES, Kwong YL (2006) Glucose-6-phosphate dehydrogenase deficiency in female octogenarians, nanogenarians, and centenarians. J Gerontol A Biol Sci Med Sci 61:1086-1089
7. Badens C, Martini N, Courrier S, DesPortes V, Touraine R, Levy N, Edery P (2006) ATRX syndrome in a girl with a heterozygous mutation in the ATRX Zn finger domain and a totally skewed X-inactivation pattern. Am J Med Genet A 140:2212-2215
8. Bahi-Buisson N, Nectoux J, Rosas-Vargas H, Milh M, Boddaert N, Girard B, Cances C, Ville D, Afenjar A, Rio M, Héron D, MAN'G Morel, Arzimanoglou A, Philippe C, Jonveaux P, Chelly J, Bienvenu T (2008) Key clinical features to identify girls with CDKL5 mutations. Brain 131:2647-2661
9. Beever CL, Stephenson MD, Peñaherrera MS, Jiang RH, Kalousek DK, Hayden M, Field L, Brown CJ, Robinson WP (2003) Skewed X-chromosome inactivation is associated with trisomy in women ascertained on the basis of recurrent spontaneous abortion or chromosomally abnormal pregnancies. Am J Hum Genet 72:399-407
10. Bennett CM, Boye E, Neufeld EJ (2008) Female monozygotic twins discordant for hemophilia A due to nonrandom X-chromosome inactivation. Am J Hematol 83:778-780
11. Bicocchi MP, Migeon BR, Pasino M, Lanza T, Bottini F, Boeri E, Molinari AC, Corsolini F, Morerio C, Acquila M (2005) Familial nonrandom inactivation linked to the X inactivation centre in heterozygotes manifesting haemophilia A. Eur J Hum Genet 13:635-640
12. Bittel DC, Theodoro MF, Kibiryeva N, Fischer W, Talebizadeh Z, Butler MG (2008) Comparison of X-chromosome inactivation patterns in multiple tissues from human females. J Med Genet 45:309-313
13. Blinkenberg EO, Brendehaug A, Sandvik AK, Vatne O, Hennekam RC, Houge G (2008) Angioma serpiginosum with oesophageal papillomatosis is an X-linked dominant condition that maps to Xp11.3-Xq12. Eur J Hum Genet 16:1027-1028
14. Bolduc V, Chagnon P, Provost S, Dubé MP, Belisle C, Gingras M, Mollica L, Busque L (2008) No evidence that skewing of X chromosome inactivation patterns is transmitted to offspring in humans. J Clin Invest 118:333-341
15. Bretherick K, Gair J, Robinson WP (2005) The association of skewed X chromosome inactivation with aneuploidy in humans. Cytogenet Genome Res 111:260-265
16. Brown CJ, Robinson WP (2000) The causes and consequences of random and non-random X chromosome inactivation in humans. Clin Genet 58:353-363
17. Burn J, Povey S, Boyd Y, Munro EA, West L, Harper K, Thomas D (1986) Duchenne muscular dystrophy in one of monozygotic twin girls. J Med Genet 23:494-500
18. Busque L, Mio R, Mattioli J, Brais E, Blais N, Lalonde Y, Maragh M, Gilliland DG (1996) Nonrandom X-inactivation patterns in normal females: lyonization ratios vary with age. Blood 88:59-65
19. Carrel L, Willard HF (2005) X-inactivation profile reveals extensive variability in X-linked gene expression in females. Nature 434:400-404
20. Carrel L, Cottle AA, Goglin KC, Willard HF (1999) A first-generation X-inactivation profile of the human X chromosome. Proc Natl Acad Sci USA 96:14440-14444
21. Cazzola M, May A, Bergamaschi G, Cerani P, Rosti V, Bishop DF (2000) Familial-skewed X-chromosome inactivation as a predisposing factor for late-onset X-linked sideroblastic anemia in carrier females. Blood 96:4363-4436
22. Chahrour M, Zoghbi HY (2007) The story of Rett syndrome: From clinic to neurobiology. Neuron 56:422-437
23. Christensen K, Kristiansen M, Hagen-Larsen H, Skytthe A, Bathum L, Jeune B, Andersen Ranberg K, Vaupel JW, Orstavik KH (2000) X-linked genetic factors regulate hematopoietic stem-cell kinetics in females. Blood 95:2449-2451
24. Christensen K, Ørstavik KH, Vaupel J (2001) The X chromosome and the female survival advantage: An example of the intersection between genetics, epidemiology and demography. Ann New York Acad Sci 954:175-183
25. Dayer AG, Bottani A, Bouchardy I, Fluss J, Antonarakis SE, Haenggeli CA, Morris MA (2007) MECP2 mutant allele in a boy with Rett syndrome and his unaffected heterozygous mother. Brain Dev 29:47-50
26. de Vries BB, Wiegers AM, Smits AP, Mohkamsing S, Duivenvoorden HJ, Fryns JP, Curfs LM, Halley DJ, Oostra BA, van den Ouweland AM, Niermeijer MF (1996) Mental status of females with an FMR1 gene full mutation. Am J Hum Genet 58:1025-1032
27. Devriendt K, Matthijs G, Legius E, Schollen E, Blockmans D, van Geet C, Degreef H, Cassiman JJ, Fryns JP (1997) Skewed X-chromosome inactivation in female carriers of dyskeratosis congenita. Am J Hum Genet 60:581-587
28. Dobyns WB, Filauro A, Tomson BN, Chan AS, Ho AW, Ting NT, Oosterwijk JC, Ober C (2004) Inheritance of most X-linked traits is not dominant or recessive, just X-linked. Am J Med Genet A 129:136-143
29. Fearon ER, Kohn DB, Winkelstein JA, Vogelstein B, Blaese RM (1988) Carrier detection in the Wiskott-Aldrich syndrome. Blood 72:1735-1739
30. Ferraris AM, Forni GL, Mangerini R, Gaetani GF (1997) Nonrandom X-chromosome inactivation in hemopoietic cells from carriers of dyskeratosis congenita. Am J Hum Genet 61:458-461
31. Franco B, Ballabio A (2006) X-inactivation and human disease: X-linked dominant male-lethal disorders. Curr Opin Genet Dev 16:254-259
32. Fusco F, Bardaro T, Fimiani G, Mercadante V, Miano MG, Falco G, Israël A, Courtois G, D'Urso M, Ursini MV (2004) Molecular analysis of the genetic defect in a large cohort of IP patients and identification of novel NEMO mutations interfering with NF-kappa B activation. Hum Mol Genet 13:1763-1773
33. Gale RE, Wheadon H, Boulos P, Linch DC (1994) Tissue specificity of X-chromosome inactivation patterns. Blood 83:2899-2905
34. Gale RE, Fielding AK, Harrison CN, Linch DC (1997) Acquired skewing of X-chromosome inactivation patterns in myeloid cells of the elderly suggests stochastic clonal loss with age. Br J Haematol 98:512-519
35. Gibbons RJ, Suthers GK, Wilkie AO, Buckle VJ, Higgs DR (1992) X-linked alpha-thalassemia/mental retardation (ATR-X) syndrome: Localization to Xq12-q21.31 by X inactivation and linkage analysis. Am J Hum Genet 51:1136-1149
36. Happle R (2006) X-chromosome inactivation: Role in skin disease expression. Acta Paediatr Suppl 95:16-23
37. Hatakeyama C, Anderson CL, Beever CL, Peñaherrera MS, Brown CJ, Robinson WP (2004) The dynamics of X-inactivation skewing as women age. Clin Genet 66:327-332
38. Huppke P, Maier EM, Warnke A, Brendel C, Laccone F, Gärtner J (2006) Very mild cases of Rett syndrome with skewed X inactivation. J Med Genet 43:814-816
39. Imai K, Shimadzu M, Kubota T, Morio T, Matsunaga T, Park YD, Yoshioka A, Nonoyama S (2006) Female hyper IgM syndrome type 1 with a chromosomal translocation disrupting CD40LG. Biochim Biophys Acta 1762:335-340
40. Knudsen GP, Pedersen J, Klingenberg O, Lygren I, Ørstavik KH (2007) Increased skewing of X chromosome inactivation with age in both blood and buccal cells. Cytogenet Genome Res 116:24-28
41. Kristiansen M, Knudsen GP, Søyland A, Westvik J, Ørstavik KH (2002) Phenotypic variation in Melnick-Needles Syndrome is not reflected in X inactivation patterns from blood or buccal smear. Am J Med Genet 108:120-127
42. Kristiansen M, Knudsen GP, Tanner SM, Robinson D, McEntagart M, Liechti-Gallati S, Ørstavik KH, Wallgren-Pettersson C (2003) X inactivation pattern in carriers of X-linked myotubular myopathy. Neuromuscul Disord 13:468-471
43. Kristiansen M, Knudsen GP, Bathum L, Naumova AK, Sørensen TI, Brix TH, Svendsen AJ, Christensen K, Kyvik KO, Ørstavik KH (2005) Twin study of genetic and aging effects on X chromosome inactivation. Eur J Hum Genet 13:599-606
44. Lacout C, Haddad E, Sabri S, Svinarchouk F, Garçon L, Capron C, Foudi A, Mzali R, Snapper SB, Louache F, Vainchenker W, Duménil D (2003) A defect in hematopoietic stem cell migration explains the nonrandom X-chromosome inactivation in carriers of Wiskott-Aldrich syndrome. Blood 102:1282-1289
45. Lanasa MC, Hogge WA, Kubik C, Blancato J, Hoffman EP (1999) Highly skewed X-chromosome inactivation is associated with idiopathic recurrent spontaneous abortion. Am J Hum Genet 65:252-254
46. Leoyklang P, Suphapeetiporn K, Wananukul S, Shotelersuk V (2008) Three novel mutations in the PORCN gene underlying focal dermal hypoplasia. Clin Genet 73:373-379
47. Leppig KA, Disteche CM (2001) Ring X and other structural X chromosome abnormalities: X inactivation and phenotype. Semin Reprod Med 19:147-157
48. Lexner MO, Bardow A, Juncker I, Jensen LG, Almer L, Kreiborg S, Hertz JM (2008) X-linked hypohidrotic ectodermal dysplasia. Genetic and dental findings in 67 Danish patients from 19 families. Clin Genet 74:252-259
49. Li SL, Ting SS, Lindeman R, Ffrench R, Ziegler JB (1998) Carrier identification in X-linked immunodeficiency diseases. J Paediatr Child Health 34:273-279
50. Lubinsky MS, Hall JG (1991) Genomic imprinting, monozygous twinning, and X inactivation. Lancet 337:1288
51. Lupski JR, Garcia CA, Zoghbi HY, Hoffman EP, Fenwick RG (1991) Discordance of muscular dystrophy in monozygotic female twins: Evidence supporting asymmetric splitting of the inner cell mass in a manifesting carrier of Duchenne dystrophy. Am J Med Genet 40:354-364
52. Lutskiy MI, Sasahara Y, Kenney DM, Rosen E, Remold-O'Donnell FS (2002) Wiskott-Aldrich syndrome in a female. Blood 100:2763-2768
53. Lyon MF (2002) X-chromosome inactivation and human genetic disease. Acta Paediatr Suppl 91:107-112
54. Lyon MF (2005) No longer 'all-or-none'. Eur J Hum Genet 13:796-797
55. Maier EM, Kammerer S, Muntau AC, Wichers M, Braun A, Roscher AA (2002) Symptoms in carriers of adrenoleukodystrophy relate to skewed X inactivation. Ann Neurol 52:683-688
56. Maier EM, Osterrieder S, Whybra C, Ries M, Gal A, Beck M, Roscher AA, Muntau AC (2006) Disease manifestations and X inactivation in heterozygous females with Fabry disease. Acta Paediatr Suppl 95:30-38
57. Marguery MC, Giordano F, Parant M, Samalens G, Levade T, Salvayre R, Maret A, Calvas P, Bourrouillou G, Cantala P, Bazex J (1993) Fabry's disease: Heterozygous form of different expression in two monozygous twin sisters. Dermatology 187:9-15
58. Matthews PM, Benjamin D, van Bakel I, Squier MV, Nicholson LV, Sewry C, Hopkin J, Brown R, Hilton-Jones D, Boyd Y, Karpati G, Brown KG, Craig IW (1995) Muscle X-inactivation patterns and dystrophin expression in Duchenne muscular dystrophy carriers. Neuromusc Disord 5:209-220
59. Migeon BR (2006) The role of X inactivation and cellular mosaicism in women's health and sex-specific diseases. J Am Med Assoc 295:1428-1433
60. Migeon B (2007) Females are MOSAICS X inactivation and sex differences in disease. Oxford University Press, Oxford
61. Migeon BR, Haisley-Royster C (1998) Familial skewed X inactivation and X-linked mutations: Unbalanced X inactivation is a powerful means to ascertain X-linked genes that affect cell proliferation. Am J Hum Genet 62:1555-1557
62. Migeon BR, Moser HW, Moser AB, Axelman J, Sillence D, Norum RA (1981) Adrenoleukodystrophy: Evidence for X linkage inactivation, and selection favoring the mutant allele in heterozygous cells. Proc Natl Acad Sci USA 78:5066-5070
63. Minks J, Robinson WP, Brown CJ (2008) A skewed view of X chromosome inactivation. J Clin Invest 118:20-23
64. Monteiro J, Derom C, Vlietinck R, Kohn N, Lesser M, Gregersen PK (1998) Commitment to X inactivation precedes the twinning event in monochorionic MZ twins. Am J Hum Genet 199:339-346
65. Moschese V, Orlandi P, Plebani A, Arvanitidis K, Fiorini M, Speletas M, Mella P, Ritis K, Sideras P, Finocchi A, Livadiotti S, Rossi P (2000) X-chromosome inactivation and mutation pattern in the Bruton's tyrosine kinase gene in patients with X-linked agammaglobulinemia. Italian XLA Collaborative Group. Mol Med 6:104-113
66. Muers MR, Sharpe JA, Garrick D, Sloane-Stanley J, Nolan PM, Hacker T, Wood WG, Higgs DR, Gibbons RJ (2007) Defining the cause of skewed X-chromosome inactivation in X-linked mental retardation by use of a mouse model. Am J Hum Genet 80:1138-1149
67. Nance WE (1990) Do twin Lyons have larger spots? Am J Hum Genet 46:646-648
68. Naumova AK, Plenge RM, Bird LM, Leppert M, Morgan K, Willard HF, Sapienza C (1996) Heritability of X chromosome-inactivation phenotype in a large family. Am J Hum Genet 58:1111-1119
69. Oostra BA, Willemsen R (2002) The X chromosome and fragile X mental retardation. Cytogenet Genome Res 99:257-264
70. Ørstavik KH (2006) Skewed X inactivation in healthy individuals and in different diseases. Acta Paediatr Suppl 95:24-29
71. Ørstavik KH, Ørstavik RE, Eiklid K, Tranebjaerg L (1996) Inheritance of skewed X inactivation in a large family with an X-linked recessive deafness syndrome. Am J Med Genet 64:31-34
72. Ørstavik KH, Ørstavik RE, Naumova AD, Adamo PA, Gedeon A, Bolhuis BA, Barth PG, Toniolo D (1998) X chromosome inactivation in carriers of Barth syndrome. Am J Hum Genet 63:1457-1463
73. Ørstavik KH, Orstavik RE, Schwartz M (1999) Skewed X chromosome inactivation in a female with haemophilia B and in her non-carrier daughter: A genetic influence on X chromosome inactivation? J Med Genet 36:865-866
74. Ørstavik KH, Scheibel E, Ingerslev J, Schwartz M (2000) Absence of correlation between X chromosome inactivation pattern and plasma concentration of factor VIII and factor IX in carriers of haemophilia A and B. Thromb Haemost 83:433-437
75. Ørstavik KH, Kristiansen M, Knudsen GP, Storhaug K, Vege A, Eiklid K, Abrahamsen TG, Smahi A, Steen-Johnsen J (2006) Novel splicing mutation in the NEMO (IKK-gamma) gene with severe immunodeficiency and heterogeneity of X-chromosome inactivation. Am J Med Genet A 140:31-33
76. Ørstavik KH, Knudsen GP, Nordgarden H, Ormerod E, Strømme P, Lazarou LP, Rosser LG, Prescott T, Houge G (2007) Severe hypohidrotic ectodermal dysplasia in a girl caused by a de novo 9;X insertion that includes XIST and disrupts the EDA gene. Am J Med Genet 143A:1510-1513
77. Parolini O, Ressmann G, Haas OA, Pawlowsky J, Gadner H, Knapp W, Holter W (1998) X-linked Wiskott-Aldrich syndrome in a girl. N Engl J Med 338:291-295
78. Pegoraro E, Schimke RN, Garcia C, Stern H, Cadaldini M, Angelini C, Barbosa E, Carroll J, Marks WA, Neville HE, Marks H, Appleton S, Toriello H, Wessel HB, Donnelly J, Bernes SM, Taber JW, Weiss L, Hoffman EP (1995) Genetic and biochemical normalization in female carriers of Duchenne muscular dystrophy: Evidence for failure of dystrophin production in dystrophin-competent myonuclei. Neurology. 45:677-690
79. Plagnol V, Uz E, Wallace C, Stevens H, Clayton D, Ozcelik T, Todd JA (2008) Extreme clonality in lymphoblastoid cell lines with implications for allele specific expression analyses. PLoS ONE 3:e2966
80. Plenge RM, Hendrich BD, Schwartz C, Arena JF, Naumova A, Sapienza C, Winter RM, Willard HF (1997) A promoter mutation in the XIST gene in two unrelated families with skewed X-chromosome inactivation. Nat Genet 17:353-356
81. Plenge RM, Tranebjaerg L, Jensen PK, Schwartz C, Willard HF (1999) Evidence that mutations in the X-linked DDP gene cause incompletely penetrant and variable skewed X inactivation. Am J Hum Genet 64:759-767
82. Plenge RM, Stevenson RA, Lubs HA, Schwartz HF, Willard CE (2002) Skewed X-chromosome inactivation is a common feature of X-linked mental retardation disorders. Am J Hum Genet 71:168-173
83. Puck JM, Willard HF (1998) X inactivation in females with X-linked disease. N Engl J Med 338:325-328
84. Raynaud M, Moizard MP, Dessay B, Briault S, Toutain A, Gendrot C, Ronce N, Moraine C (2000) Systematic analysis of X-inactivation in 19 XLMR families: Extremely skewed profiles in carriers in three families. Eur J Hum Genet 8:253-258
85. Redonnet-Vernhet I, Ploos van Amstel JK, Jansen RP, Wevers RA, Salvayre R, Levade T (1996) Uneven X inactivation in a female monozygotic twin pair with Fabry disease and discordant expression of a novel mutation in the alpha-galactosidase A gene. J Med Genet 33:682-688
86. Renault NK, Dyack S, Dobson MJ, Costa T, Lam WL, Greer WL (2007) Heritable skewed X-chromosome inactivation leads to haemophilia A expression in heterozygous females. Eur J Hum Genet 15:628-630
87. Richards CS, Watkins SC, Hoffman EP, Schneider NR, Milsark IW, Katz KS, Cook JD, Kunkel LM, Cortada JM (1990) Skewed X inactivation in a female MZ twin results in Duchenne muscular dystrophy. Am J Hum Genet 46:672-681
88. Robertson SP, Twigg SR, Sutherland-Smith AJ, Biancalana V, Gorlin RJ, Horn D, Kenwrick SJ, Kim CA, Morava E, Newbury-Ecob R, Orstavik KH, Quarell OW, Schwartz CE, Shears DJ, Suri M, Kendrick-Jones J, Wilkie AO, OPD-spectrum Disorders Clinical Collaborative Group (2003) Localized mutations in the gene encoding the cytoskeletal protein filamin A cause diverse malformations in humans. Nat Genet 33:487-491
89. Robertson SP, Jenkins ZA, Morgan T, Adès L, Aftimos S, Boute O, Fiskerstrand T, Garcia-Miñaur S, Grix A, Green A, Der Kaloustian V, Lewkonia R, McInnes B, van Haelst MM, Mancini G, Illés T, Mortier G, Newbury-Ecob R, Nicholson L, Scott CI, Ochman K, Brozek I, Shears DJ, Superti-Furga A, Suri M, Whiteford M, Wilkie AO, Krakow D (2006) Frontometaphyseal dysplasia: Mutations in FLNA and phenotypic diversity. Am J Med Genet A 140:1726-1736
90. Robinson WP, Beever C, Brown CJ, Stephenson MD (2001) Skewed X inactivation and recurrent spontaneous abortion. Semin Reprod Med 19:175-181
91. Sandovici I, Naumova AK, Leppert M, Linares Y, Sapienza C (2004) A longitudinal study of X-inactivation ratio in human females. Hum Genet 115:387-392
92. Sangha KK, Stephenson MD, Brown CJ, Robinson W (1999) Extremely skewed X-chromosome inactivation is increased in women with recurrent spontaneous abortion. Am J Hum Genet 65:913-917
93. Satoh M, Ogikubo S, Yoshizawa-Ogasawara A (2008) Correlation between clinical phenotypes and X-inactivation patterns in six female carriers with heterozygote vasopressin type 2 receptor gene mutations. Endocr J 55:277-284
94. Schluth C, Cossée M, Girard-Lemaire F, Carelle N, Dollfus H, Jeandidier E, Flori E (2007) Phenotype in X chromosome rearrangements: pitfalls of X inactivation study. Pathol Biol (Paris) 55:29-36
95. Schmidt M, Du Sart D (1992) Functional disomies of the X chromosome influence the cell selection and hence the X inactivation pattern in females with balanced X-autosome translocations: A review of 122 cases. Am J Med Genet 42:161-169
96. Sharp A, Robinson D, Jacobs P (2000) Age- and tissue-specific variation of X chromosome inactivation ratios in normal women. Hum Genet 107:343-349
97. Sumita DR, Vainzof M, Campiotto S, Cerqueira AM, Cánovas M, Otto PA, Passos-Bueno MR, Zatz M (1998) Absence of correlation between skewed X inactivation in blood and serum creatine-kinase levels in Duchenne/ Becker female carriers. Am J Med Genet 80:356-361
98. Sun BK, Tsao H (2008) X-chromosome inactivation, skin disease. J Invest Dermatol 128:2753-2759
99. Swierczek SI, Agarwal N, Nussenzveig RH, Rothstein G, Wilson A, Artz A, Prchal JT (2008) Hematopoiesis is not clonal in healthy elderly women. Blood 112:3186-3193
100. Tanner SM, Orstavik KH, Kristiansen M, Lev D, Lerman-Sagie T, Sadeh M, Liechti-Gallati S (1999) Skewed X-inactivation in a manifesting carrier of X-linked myotubular myopathy and in her non-manifesting carrier mother. Hum Genet 104:249-253
101. Thauvin-Robinet C, Cossée M, Cormier-Daire V, Van Maldergem L, Toutain A, Alembik Y, Bieth E, Layet V, Parent P, David A, Goldenberg A, Mortier G, Héron D, Sagot P, Bouvier AM, Huet F, Cusin V, Donzel A, Devys D, Teyssier JR, Faivre L (2006) Clinical, molecular, and genotype-phenotype correlation studies from 25 cases of oral-facial-digital syndrome type 1: A French and Belgian collaborative study. J Med Genet 43:54-61
102. Tiberio G (1994) MZ female twins discordant for X-linked diseases: A review. Acta Genet Med Gemellol 43:207-214
103. Turner G, Lower KM, White SM, Delatycki M, Lampe AK, Wright M, Smith JC, Kerr B, Schelley S, Hoyme HE, De Vries BB, Kleefstra T, Grompe M, Cox B, Gecz J, Partington M (2004) The clinical picture of the Börjeson-Forssman-Lehmann syndrome in males and heterozygous females with PHF6 mutations. Clin Genet 65:226-232
104. Twigg SR, Kan R, Babbs C, Bochukova EG, Robertson SP, Wall SA, Morriss-Kay GM, Wilkie AO (2004) Mutations of ephrin-B1 (EFNB1), a marker of tissue boundary formation, cause craniofrontonasal syndrome. Proc Natl Acad Sci USA 101:8652-8657
105. Van den Veyver IB (2001) Skewed X inactivation in X-linked disorders. Semin Reprod Med 19:183-191
106. Van Esch H, Bauters M, Ignatius J, Jansen M, Raynaud M, Hollanders K, Lugtenberg D, Bienvenu T, Jensen LR, Gecz J, Moraine C, Marynen P, Fryns JP, Froyen G (2005) Duplication of the MECP2 region is a frequent cause of severe mental retardation and progressive neurological symptoms in males. Am J Hum Genet 77:442-453
107. Vickers MA, McLeod E, Spector TD, Wilson IJ (2001) Assessment of mechanism of acquired skewed X inactivation by analysis of twins. Blood 97:1274-1281
108. Vulliamy TJ, Knight SW, Dokal I, Mason PJ (1997) Skewed X-inactivation in carriers of X-linked dyskeratosis congenita. Blood 90:2213-2216
109. Wada T, Sugie H, Fukushima Y, Saitoh S (2005) Non-skewed X-inactivation may cause mental retardation in a female carrier of X-linked alpha-thalassemia/mental retardation syndrome (ATR-X): X-inactivation study of nine female carriers of ATR-X. Am J Med Genet A 138:18-20
110. Winchester B, Young E, Geddes S, Genet S, Hurst J, Middleton-Price H, Williams N, Webb M, Habel A, Malcolm S (1992) Female twin with Hunter disease due to nonrandom inactivation of the X-chromosome: A consequence of twinning. Am J Med Genet 44:834-838
111. Yorifuji T, Muroi J, Uematsu A, Tanaka K, Kiwaki K, Endo F, Matsuda I, Nagasaka H, Furusho K (1998) X-inactivation pattern in the liver of a manifesting female with ornithine transcarbamylase (OTC) deficiency. Clin Genet 54:349-353
112. Yoshioka M, Yorifuji T, Mituyoshi I (1998) Skewed X inactivation in manifesting carriers of Duchenne muscular dystrophy. Clin Genet 53:102-107