Twin Studies in Sleep Medicine: A Review

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Catherine A. McCall, MD Glen E. Duncan, PhD, RCEP Nathaniel F. Watson MD, MSc


Sleep and sleep disorders are complex phenotypes with genetic, epigenetic, and environmental influences. Twin studies allow researchers to parse out how these factors influence variability in sleep outcomes such as sleep duration and quality, chronotype, and disorders such as insomnia, hypersomnia, sleep apnea, sleep-related movement disorders, and parasomnias. Twin studies assess the overlap in genetic influences for sleep variance and other medical and psychiatric disorders and allow exploration of gene-environment interactions. Longitudinal twin studies demonstrate how these interactions change over the course of a lifetime. In general, twin studies demonstrate that the heritability of common sleep measures such as duration, quality, and chronotype is about 30-50%; however, this can vary widely between samples according to age, sex, comorbidities, and geographic location. Similarly, the heritability of sleep disorders including insomnia, obstructive sleep apnea, and parasomnias is also around 30-50%, with higher estimates for disorders known to run in families, such as sleepwalking. Heritability estimates for medical and psychiatric problems including obesity, depression, post-traumatic stress disorder, and mortality are higher with short sleep duration (typically < 7 h/n), suggesting that short sleep activates disease-related gene expression. Significant genetic overlap exists between insomnia and issues such as obesity, chronic pain, depression, and psychosis. In this review, we describe the major findings of twin studies related to sleep and how they impact our understanding of this critical component of health and disease.


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MCCALL, Catherine A.; DUNCAN, Glen E.; WATSON MD, MSC, Nathaniel F.. Twin Studies in Sleep Medicine: A Review. Medical Research Archives, [S.l.], v. 9, n. 7, aug. 2021. ISSN 2375-1924. Available at: <>. Date accessed: 19 may 2022. doi:
Review Articles


1. Dashti HS, Jones SE, Wood AR, et al. Genome-wide association study identifies genetic loci for self-reported habitual sleep duration supported by accelerometer-derived estimates. Nat Commun. 2019;10(1). doi:10.1038/s41467-019-08917-4
2. Ashbrook LH, Krystal AD, Fu YH, Ptáček LJ. Genetics of the human circadian clock and sleep homeostat. Neuropsychopharmacology. 2020;45(1):45-54. doi:10.1038/s41386-019-0476-7
3. Ambrosius U, Lietzenmaier S, Wehrle R, et al. Heritability of Sleep Electroencephalogram. Biol Psychiatry. 2008;64(4):344-348. doi:10.1016/j.biopsych.2008.03.002
4. Magee CA, Robinson L, Keane C. Sleep quality subtypes predict health-related quality of life in children. Sleep Med. 2017;35:67-73. doi:10.1016/j.sleep.2017.04.007
5. Magee CA, Reddy P, Robinson L, McGregor A. Sleep quality subtypes and obesity. Heal Psychol. 2016;35(12):1289-1297. doi:10.1037/hea0000370
6. Blanken TF, Benjamins JS, Borsboom D, et al. Insomnia disorder subtypes derived from life history and traits of affect and personality. The Lancet Psychiatry. 2019;6(2):151-163. doi:10.1016/S2215-0366(18)30464-4
7. Zinchuk A V., Gentry MJ, Concato J, Yaggi HK. Phenotypes in obstructive sleep apnea: A definition, examples and evolution of approaches. Sleep Med Rev. 2017;35:113-123. doi:10.1016/j.smrv.2016.10.002
8. Champion D, Bui M, Aouad P, et al. Contrasting painless and painful phenotypes of pediatric restless legs syndrome: a twin family study. Sleep Med. 2020;75:361-367. doi:10.1016/j.sleep.2020.08.024
9. Kalmbach DA, Schneider LD, Cheung J, et al. Genetic basis of chronotype in humans: Insights from three landmark gwas. Sleep. 2017;40(2). doi:10.1093/sleep/zsw048
10. Cruz-Fierro N, Martínez-Fierro M, Cerda-Flores RM, et al. The phenotype, psychotype and genotype of bruxism. Biomed Reports. 2018;8(3):264-268. doi:10.3892/br.2018.1041
11. Boomsma D, Busjahn A, Peltonen L. Classical twin studies and beyond. Nat Rev Genet. 2002;3(11):872-882. doi:10.1038/nrg932
12. Kocevska D, Barclay NL, Bramer WM, Gehrman PR, Van Someren EJW. Heritability of sleep duration and quality: A systematic review and meta-analysis. Sleep Med Rev. 2021;59. doi:10.1016/j.smrv.2021.101448
13. Madrid-Valero JJ, Rubio-Aparicio M, Gregory AM, Sánchez-Meca J, Ordoñana JR. Twin studies of subjective sleep quality and sleep duration, and their behavioral correlates: Systematic review and meta-analysis of heritability estimates. Neurosci Biobehav Rev. 2020;109:78-89. doi:10.1016/j.neubiorev.2019.12.028
14. Barclay NL, Kocevska D, Bramer WM, Van Someren EJW, Gehrman P. The heritability of insomnia: A meta-analysis of twin studies. Genes, Brain Behav. April 2020. doi:10.1111/gbb.12717
15. Partinen M, Hublin C, Kaprio J, Koskenvuo M, Guilleminault C. Twin studies in narcolepsy. In: Sleep. Vol 17. Associated Professional Sleep Societies,LLC; 1994. doi:10.1093/sleep/17.suppl_8.s13
16. Desai A V., Cherkas LF, Spector TD, Williams AJ. Genetic influences in self-reported symptoms of obstructive sleep apnoea and restless legs: A twin study. Twin Res. 2004;7(6):589-595. doi:10.1375/1369052042663841
17. Hur YM. Stability of genetic influence on morningness-eveningness: A cross-sectional examination of South Korean twins from preadolescence to young adulthood. J Sleep Res. 2007;16(1):17-23. doi:10.1111/j.1365-2869.2007.00562.x
18. Åkerstedt T, Narusyte J, Alexanderson K, Svedberg P. Sleep Duration, Mortality, and Heredity—A Prospective Twin Study. Sleep. 2017;40(10). doi:10.1093/sleep/zsx135
19. Watson NF, Harden KP, Buchwald D, et al. Sleep duration and body mass index in twins: A gene-environment interaction. Sleep. 2012;35(5):597-603. doi:10.5665/sleep.1810
20. Watson NF, Harden KP, Buchwald D, et al. Sleep duration and depressive symptoms: A gene-environment interaction. Sleep. 2014;37(2):351-358. doi:10.5665/sleep.3412
21. McCall CA, Turkheimer E, Tsang S, Avery A, Duncan GE, Watson NF. Sleep duration and post-traumatic stress disorder symptoms: A twin study. Sleep. 2019;42(12). doi:10.1093/sleep/zsz179
22. Barclay NL, Eley TC, Buysse DJ, Archer SN, Gregory AM. Diurnal preference and sleep quality: Same genes? A study of young adult twins. Chronobiol Int. 2010;27(2):278-296. doi:10.3109/07420521003663801
23. Neale M, Cardon L. Methodology for Genetic Studies of Twins and Families. Dordrecht: Kluwer Academic Publishers-Plenum Publishers; 1992.
24. Turkheimer E, Harden K. Behavior genetic research methods. In: Reis H, Judd C, eds. Handbook of Research Methods in Social and Personality Psychology. 2nd ed. Cambridge: Cambridge University Press; 2014:159-187.
25. Grandner M, Mullington JM, Hashmi SD, Redeker NS, Watson NF, Morgenthaler TI. Sleep duration and hypertension: Analysis of > 700,000 adults by age and sex. J Clin Sleep Med. 2018;14(6):1031-1039. doi:10.5664/jcsm.7176
26. Barger LK, Rajaratnam SMW, Cannon CP, et al. Short sleep duration, obstructive sleep apnea, shiftwork, and the risk of adverse cardiovascular events in patients after an acute coronary syndrome. J Am Heart Assoc. 2017;6(10). doi:10.1161/JAHA.117.006959
27. Yaggi HK, Araujo AB, McKinlay JB. Sleep duration as a risk factor for the development of type 2 diabetes. Diabetes Care. 2006;29(3):657-661.
28. Czeisler CA, Wickwire EM, Barger LK, et al. Sleep-deprived motor vehicle operators are unfit to drive: a multidisciplinary expert consensus statement on drowsy driving. Sleep Heal. 2016;2(2):94-99. doi:10.1016/j.sleh.2016.04.003
29. Grandner MA, Hale L, Moore M, Patel NP. Mortality associated with short sleep duration: The evidence, the possible mechanisms, and the future. Sleep Med Rev. 2010;14(3):191-203. doi:10.1016/j.smrv.2009.07.006
30. Barclay NL, Eley TC, Buysse DJ, Rijsdijk F V., Gregory AM. Genetic and environmental influences on different components of the Pittsburgh sleep quality index and their overlap. Sleep. 2010;33(5):659-668. doi:10.1093/sleep/33.5.659
31. Gregory AM, Rijsdijk F V., Eley TC. A twin-study of sleep difficulties in school-aged children. Child Dev. 2006;77(6):1668-1679. doi:10.1111/j.1467-8624.2006.00966.x
32. Ohayon MM, Carskadon MA, Guilleminault C, Vitiello M V. Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: developing normative sleep values across the human lifespan. Sleep. 2004;27(7):1255-1273.
33. Watson NF, Badr MS, Belenky G, et al. Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society on the Recommended Amount of Sleep for a Healthy Adult: Methodology and Discussion. Sleep. 2015;38(8):1161-1183. doi:10.5665/sleep.4886
34. Hirshkowitz M, Whiton K, Albert SM, et al. National Sleep Foundation’s updated sleep duration recommendations: Final report. Sleep Heal. 2015;1(4):233-243. doi:10.1016/j.sleh.2015.10.004
35. Barclay NL, Gregory AM. Quantitative genetic research on sleep: A review of normal sleep, sleep disturbances and associated emotional, behavioural, and health-related difficulties. Sleep Med Rev. 2013;17(1):29-40. doi:10.1016/j.smrv.2012.01.008
36. Barclay NL, Watson NF, Buchwald D, Goldberg J. Moderation of genetic and environmental influences on diurnal preference by age in adult twins. Chronobiol Int. 2014;31(2):222-231. doi:10.3109/07420528.2013.842924
37. Plomin R. Child Development and Molecular Genetics: 14Years Later. Child Dev. 2013;84(1):104-120. doi:10.1111/j.1467-8624.2012.01757.x
38. Watson NF, Horn E, Duncan GE, Buchwald D, Vitiello M V, Turkheimer E. Sleep Duration and Area-Level Deprivation in Twins. Sleep. 2016;39(1):67-77. doi:10.5665/sleep.5320
39. Watson NF, Buchwald D, Delrow JJ, et al. Transcriptional signatures of sleep duration discordance in monozygotic twins. Sleep. 2017;40(1). doi:10.1093/sleep/zsw019
40. Wrede JE, Mengel-From J, Buchwald D, et al. Mitochondrial DNA copy number in sleep duration discordant monozygotic twins. Sleep. 2015;38(10):1655-1658A. doi:10.5665/sleep.5068
41. Barnes JC, Meldrum RC. The Impact of Sleep Duration on Adolescent Development: A Genetically Informed Analysis of Identical Twin Pairs. J Youth Adolesc. 2015;44(2):489-506. doi:10.1007/s10964-014-0137-4
42. Butkovic A, Vukasovic T, Bratko D. Sleep duration and personality in Croatian twins. J Sleep Res. 2014;23(2):153-158. doi:10.1111/jsr.12101
43. Boomsma DI, Van Someren EJW, Beem AL, De Geus EJC, Willemsen G. Sleep during a regular week night: A twin-sibling study. Twin Res Hum Genet. 2008;11(5):538-545. doi:10.1375/twin.11.5.538
44. Barclay NL, Eley TC, Buysse DJ, Maughan B, Gregory AM. Nonshared environmental influences on sleep quality: A study of monozygotic twin differences. Behav Genet. 2012;42(2):234-244. doi:10.1007/s10519-011-9510-1
45. Pinheiro MB, Morosoli JJ, Ferreira ML, et al. Genetic and environmental contributions to sleep quality and low back pain: A population-based twin study. Psychosom Med. 2018;80(3):263-270. doi:10.1097/PSY.0000000000000548
46. Andreucci A, Madrid-Valero JJ, Ferreira PH, Ordoñana JR. Sleep quality and chronic neck pain: A cotwin study. J Clin Sleep Med. 2020;16(5):679-687. doi:10.5664/jcsm.8316
47. Madrid-Valero JJ, Martínez-Selva JM, Ordoñana JR. Sleep quality and body mass index: a co-twin study. J Sleep Res. 2017;26(4):461-467. doi:10.1111/jsr.12493
48. Gregory AM, Agnew-Blais JC, Matthews T, Moffitt TE, Arseneault L. ADHD and Sleep Quality: Longitudinal Analyses From Childhood to Early Adulthood in a Twin Cohort. J Clin Child Adolesc Psychol. 2017;46(2):284-294. doi:10.1080/15374416.2016.1183499
49. Taylor MJ, Gregory AM, Freeman D, Ronald A. Do sleep disturbances and psychotic-like experiences in adolescence share genetic and environmental influences? J Abnorm Psychol. 2015;124(3):674-684. doi:10.1037/abn0000057
50. Gasperi M, Herbert M, Schur E, Buchwald D, Afari N. Genetic and Environmental Influences on Sleep, Pain, and Depression Symptoms in a Community Sample of Twins. Psychosom Med. 2017;79(6):646-654. doi:10.1097/PSY.0000000000000456
51. Madrid-Valero JJ, Ronald A, Shakeshaft N, Schofield K, Malanchini M, Gregory AM. Sleep quality, insomnia, and internalizing difficulties in adolescents: Insights from a twin study. Sleep. 2020;43(2). doi:10.1093/sleep/zsz229
52. Gregory AM, Buysse DJ, Willis TA, et al. Associations between sleep quality and anxiety and depression symptoms in a sample of young adult twins and siblings. J Psychosom Res. 2011;71(4):250-255. doi:10.1016/j.jpsychores.2011.03.011
53. Medda E, Alessandri G, Delfino D, et al. Adolescents self-reported sleep quality and emotional regulation: A discordant twin study. Ann Ist Super Sanita. 2019;55(2):118-123. doi:10.4415/ANN_19_02_03
54. Hu Y, Visser M, Kaiser S. Perceived Stress and Sleep Quality in Midlife and Later: Controlling for Genetic and Environmental Influences. Behav Sleep Med. 2020;18(4):537-549. doi:10.1080/15402002.2019.1629443
55. Lopez-Minguez J, Ordoñana JR, Sánchez-Romera JF, Madrid JA, Garaulet M. Circadian system heritability as assessed by wrist temperature: A twin study. Chronobiol Int. 2015;32(1):71-80. doi:10.3109/07420528.2014.955186
56. Linkowski P, Van Onderbergen A, Kerkhofs M, Bosson D, Mendlewicz J, Van Cauter E. Twin study of the 24-h cortisol profile: Evidence for genetic control of the human circadian clock. Am J Physiol - Endocrinol Metab. 1993;264(2 27-2). doi:10.1152/ajpendo.1993.264.2.e173
57. Matsumoto D, Inui F, Honda C, et al. Heritability and environmental correlation of phase angle with anthropometric measurements: A twin study. Int J Environ Res Public Health. 2020;17(21):1-10. doi:10.3390/ijerph17217810
58. Hallam KT, Olver JS, Chambers V, Begg DP, McGrath C, Norman TR. The heritability of melatonin secretion and sensitivity to bright nocturnal light in twins. Psychoneuroendocrinology. 2006;31(7):867-875. doi:10.1016/j.psyneuen.2006.04.004
59. Barclay NL, Eley TC, Buysse DJ, Archer SN, Gregory AM. Diurnal preference and sleep quality: Same genes? A study of young adult twins. Chronobiol Int. 2010;27(2):278-296. doi:10.3109/07420521003663801
60. Vink JM, Vink JM, Groot AS, Kerkhof GA, Boomsma DI. Genetic analysis of morningness and eveningness. Chronobiol Int. 2001;18(5):809-822. doi:10.1081/CBI-100107516
61. Koskenvuo M, Hublin C, Partinen M, Heikkilä K, Kaprio J. Heritability of diurnal type: A nationwide study of 8753 adult twin pairs. J Sleep Res. 2007;16(2):156-162. doi:10.1111/j.1365-2869.2007.00580.x
62. Barclay NL, Eley TC, Parsons MJ, Willis TA, Gregory AM. Monozygotic twin differences in non-shared environmental factors associated with chronotype. J Biol Rhythms. 2013;28(1):51-61. doi:10.1177/0748730412468698
63. Wong CCY, Parsons MJ, Lester KJ, et al. Epigenome-Wide DNA Methylation Analysis of Monozygotic Twins Discordant for Diurnal Preference. Twin Res Hum Genet. 2015;18(6):662-669. doi:10.1017/thg.2015.78
64. Toomey R, Panizzon MS, Kremen WS, Franz CE, Lyons MJ. A twin-study of genetic contributions to morningness-eveningness and depression. Chronobiol Int. 2015;32(3):303-309. doi:10.3109/07420528.2014.971366
65. Broms U, Kaprio J, Hublin C, Partinen M, Madden PAF, Koskenvuo M. Evening types are more often current smokers and nicotine-dependent-a study of Finnish adult twins. Addiction. 2011;106(1):170-177. doi:10.1111/j.1360-0443.2010.03112.x
66. Dickerman BA, Markt SC, Koskenvuo M, et al. Sleep disruption, chronotype, shift work, and prostate cancer risk and mortality: a 30-year prospective cohort study of Finnish twins. Cancer Causes Control. 2016;27(11):1361-1370. doi:10.1007/s10552-016-0815-5
67. World Health Organization, International Agency for Research on Cancer. IARC Monographs Meeting 124: Night Shift Work. Lyon, France; 2019.
68. American Academy of Sleep Medicine. The International Classification of Sleep Disorders - Third Edition (ICSD-3). Darien, IL: American Academy of Sleep Medicine; 2014.
69. Madrid-Valero JJ, Rubio-Aparicio M, Gregory AM, Sánchez-Meca J, Ordoñana JR. The heritability of insomnia: Systematic review and meta-analysis of twin studies. Sleep Med Rev. 2021;58:101437. doi:10.1016/j.smrv.2021.101437
70. Schneider MN, Denis D, Buysse DJ, Kovas Y, Gregory AM. Associations between pre-sleep arousal and insomnia symptoms in early adulthood: A twin and sibling study. Sleep. 2019;42(5). doi:10.1093/sleep/zsz029
71. Drake CL, Friedman NP, Wright KP, Roth T. Sleep reactivity and insomnia: Genetic and environmental influences. Sleep. 2011;34(9):1179-1188. doi:10.5665/SLEEP.1234
72. Spielman AJ, Caruso LS, Glovinsky P. A behavioral perspective on insomnia treatment. Psychiatr Clin North Am. 1987;10(4):541-543.
73. Gregory AM, Rijsdijk F V., Eley TC, et al. A longitudinal twin and sibling study of associations between insomnia and depression symptoms in young adults. Sleep. 2016;39(11):1985-1992. doi:10.5665/sleep.6228
74. Zhang J, Lam SP, Li SX, et al. Insomnia, sleep quality, pain, and somatic symptoms: Sex differences and shared genetic components. Pain. 2012;153(3):666-673. doi:10.1016/j.pain.2011.12.003
75. Gehrman PR, Meltzer LJ, Moore M, et al. Heritability of insomnia symptoms in youth and their relationship to depression and anxiety. Sleep. 2011;34(12):1641-1646. doi:10.5665/sleep.1424
76. Watson NF, Goldberg J, Arguelles L, Buchwald D. Genetic and environmental influences on insomnia, daytime sleepiness, and obesity in twins. Sleep. 2006;29(5):645-649. doi:10.1093/sleep/29.5.645
77. Cox RC, Taylor S, Strachan E, Olatunji BO. Insomnia and posttraumatic stress symptoms: Evidence of shared etiology. Psychiatry Res. 2020;286. doi:10.1016/j.psychres.2019.112548
78. Carmelli D, Bliwise DL, Swan GE, Reed T. Genetic factors in self-reported snoring and excessive daytime sleepiness: A twin study. Am J Respir Crit Care Med. 2001;164(6):949-952. doi:10.1164/ajrccm.164.6.2012001
79. Chabas D, Taheri S, Renier C, Mignot E. The Genetics of Narcolepsy. Annu Rev Genomics Hum Genet. 2003;4:459-483. doi:10.1146/annurev.genom.4.070802.110432
80. Taheri S, Mignot E. The genetics of sleep disorders. Lancet Neurol. 2002;1(4):242-250. doi:10.1016/S1474-4422(02)00103-5
81. Barateau L, Liblau R, Peyron C, Dauvilliers Y. Narcolepsy Type 1 as an Autoimmune Disorder: Evidence, and Implications for Pharmacological Treatment. CNS Drugs. 2017;31(10):821-834. doi:10.1007/s40263-017-0464-6
82. Liblau RS, Vassalli A, Seifinejad A, Tafti M. Hypocretin (orexin) biology and the pathophysiology of narcolepsy with cataplexy. Lancet Neurol. 2015;14(3):318-328. doi:10.1016/S1474-4422(14)70218-2
83. Goulart LI, Pedrazolli M, Martori AH, Eckeli A, Sander HH. Narcolepsy with cataplexy in monozygotic twins. Sleep Sci. 2014;7(1):62-64. doi:10.1016/j.slsci.2014.01.001
84. Pollmacher T, Schulz H, Geisler P, Kiss E, Albert ED, Schwarzfischer F. DR2-positive monozygotic twins discordant for narcolepsy. Sleep. 1990;13(4):336-343. doi:10.1093/sleep/13.4.336
85. Ito H, Mori K, Mori T, Goji A, Kagami S. Case of early childhood-onset narcolepsy with cataplexy: Comparison with a monozygotic co-twin. Pediatr Int. 2014;56(5):789-793. doi:10.1111/ped.12377
86. Honda M, Honda Y, Uchida S, Miyazaki SI, Tokunaga K. Monozygotic twins incompletely concordant for narcolepsy. Biol Psychiatry. 2001;49(11):943-947. doi:10.1016/S0006-3223(01)01090-3
87. Ueno T, Fukuhara A, Ikegami A, Ohishi F, Kume K. Monozygotic twins concordant for Kleine-Levin syndrome. BMC Neurol. 2012;12. doi:10.1186/1471-2377-12-31
88. Szily M, Tarnoki AD, Tarnoki DL, et al. Genetic influences on the onset of obstructive sleep apnoea and daytime sleepiness: A twin study. Respir Res. 2019;20(1). doi:10.1186/s12931-019-1095-x
89. Carmelli D, Colrain IM, Swan GE, Bliwise DL. Genetic and environmental influences in sleep-disordered breathing in older male twins. Sleep. 2004;27(5):917-922. doi:10.1093/sleep/27.5.917
90. Madrid-Valero JJ, Barclay NL, Rowe R, et al. Association between symptoms of sleep apnea and problem behaviors in young adult twins and siblings. Psychol Med. 2020. doi:10.1017/S0033291719004070
91. Ondo WG, Dat Vuong K, Wang Q. Restless legs syndrome in monozygotic twins: Clinical correlates. Neurology. 2000;55(9):1404-1406. doi:10.1212/wnl.55.9.1404
92. Xiong L, Jang K, Montplaisir J, et al. Canadian restless legs syndrome twin study. Neurology. 2007;68(19):1631-1633. doi:10.1212/01.wnl.0000261016.90374.fd
93. Champion D, Pathirana S, Flynn C, et al. Growing pains: Twin family study evidence for genetic susceptibility and a genetic relationship with restless legs syndrome. Eur J Pain (United Kingdom). 2012;16(9):1224-1231. doi:10.1002/j.1532-2149.2012.00130.x
94. Hublin C, Kaprio J, Partinen M, Koskenvuo M. Sleep bruxism based on self-report in a nationwide twin cohort. J Sleep Res. 1998;7(1):61-67. doi:10.1046/j.1365-2869.1998.00091.x
95. Rintakoski K, Hublin C, Lobbezoo F, Rose RJ, Kaprio J. Genetic factors account for half of the phenotypic variance in liability to sleep-related bruxism in young adults: A nationwide finnish twin cohort study. Twin Res Hum Genet. 2012;15(6):714-719. doi:10.1017/thg.2012.54
96. Horowitz SL. Clinical Aspects of Genetic Research in Dentistry. J Dent Res. 1963;42(6):1330-1343. doi:10.1177/00220345630420060901
97. Lindqvist B. Bruxism in twins. Acta Odontol Scand. 1974;32(3):177-187. doi:10.3109/00016357409002546
98. Ahlberg J, Piirtola M, Lobbezoo F, et al. Correlates and genetics of self-reported sleep and awake bruxism in a nationwide twin cohort. J Oral Rehabil. 2020;47(9):1110-1119. doi:10.1111/joor.13042
99. Michalowicz BS, Pihlstrom BL, Hodges JS, Bouchard TJ. No heritability of temporomandibular joint signs and symptoms. J Dent Res. 2000;79(8):1573-1578. doi:10.1177/00220345000790080801
100. Rintakoski K, Ahlberg J, Hublin C, et al. Bruxism is associated with nicotine dependence: A nationwide Finnish Twin Cohort study. Nicotine Tob Res. 2010;12(12):1254-1260. doi:10.1093/ntr/ntq190
101. Bakwin H. SLEEP-WALKING IN TWINS. Lancet. 1970;296(7670):446-447. doi:10.1016/S0140-6736(70)90058-9
102. Hublin C, Kaprio J, Partinen M, Heikkilä K, Koskenvuo M. Prevalence and genetics of sleepwalking: A population-based twin study. Neurology. 1997;48(1):177-181. doi:10.1212/WNL.48.1.177
103. Nguyen BH, Pérusse D, Paquet J, et al. Sleep terrors in children: A prospective study of twins. Pediatrics. 2008;122(6). doi:10.1542/peds.2008-1303
104. De Ocampo J, Foldvary N, Dinner DS, Golish J. Sleep-related eating disorder in fraternal twins. Sleep Med. 2002;3(6):525-526. doi:10.1016/S1389-9457(02)00137-5
105. Hublin C, Kaprio J, Partinen M, Koskenvuo M. Nightmares: Familial aggregation and association with psychiatric disorders in a nationwide twin cohort. Am J Med Genet - Neuropsychiatr Genet. 1999;88(4):329-336. doi:10.1002/(SICI)1096-8628(19990820)88:4<329::AID-AJMG8>3.0.CO;2-E
106. Breitenstein RS, Doane LD, Clifford S, Lemery-Chalfant K. Children’s sleep and daytime functioning: Increasing heritability and environmental associations with sibling conflict. Soc Dev. 2018;27(4):967-983. doi:10.1111/sode.12302
107. Brescianini S, Volzone A, Fagnani C, et al. Genetic and environmental factors shape infant sleep patterns: A study of 18-month-old twins. Pediatrics. 2011;127(5). doi:10.1542/peds.2010-0858
108. De Castro JM. The influence of heredity on self-reported sleep patterns in free-living humans. Physiol Behav. 2002;76(4-5):479-486. doi:10.1016/S0031-9384(02)00699-6
109. Fisher A, Van Jaarsveld CHM, Llewellyn CH, Wardle J. Genetic and environmental influences on infant sleep. Pediatrics. 2012;129(6):1091-1096. doi:10.1542/peds.2011-1571
110. Gedda L, Brenci G. Sleep and dream characteristics in twins. Acta Genet Med Gemellol (Roma). 1979;28(3):237-239. doi:10.1017/S0001566000009089
111. Genderson MR, Rana BK, Panizzon MS, et al. Genetic and environmental influences on sleep quality in middle-aged men: A twin study. J Sleep Res. 2013;22(5):519-526. doi:10.1111/jsr.12048
112. Gehrman PR, Ghorai A, Goodman M, et al. Twin-based heritability of actimetry traits. Genes, Brain Behav. 2019;18(5). doi:10.1111/gbb.12569
113. Heath AC, Kendler KS, Eaves LJ, Martin NG. Evidence for genetic influences on sleep disturbance and sleep pattern in twins. Sleep. 1990;13(4):318-335. doi:10.1093/sleep/13.4.318
114. Hublin C, Partinen M, Koskenvuo M, Kaprio J. Genetic factors in evolution of sleep length - a longitudinal twin study in Finnish adults. J Sleep Res. 2013;22(5):513-518. doi:10.1111/jsr.12051
115. Inderkum AP, Tarokh L. High heritability of adolescent sleep-wake behavior on free, but not school days: A long-term twin study. Sleep. 2018;41(3). doi:10.1093/sleep/zsy004
116. Liu R, Liu X, Arguelles LM, et al. A population-based twin study on sleep duration and body composition. Obesity. 2012;20(1):192-199. doi:10.1038/oby.2011.274
117. Lopez-Minguez J, Morosoli JJ, Madrid JA, Garaulet M, Ordoñana JR. Heritability of siesta and night-time sleep as continuously assessed by a circadian-related integrated measure. Sci Rep. 2017;7(1). doi:10.1038/s41598-017-12460-x
118. Madrid-Valero JJ, Sánchez-Romera JF, Gregory AM, Martínez-Selva JM, Ordoñana JR. Heritability of sleep quality in a middle-aged twin sample from Spain. Sleep. 2018;41(9). doi:10.1093/sleep/zsy110
119. Partinen M, Kaprio J, Koskenvuo M, Putkonen P, Langinvainio H. Genetic and environmental determination of human sleep. Sleep. 1983;6(3):179-185. doi:10.1093/sleep/6.3.179
120. Sletten TL, Rajaratnam SMW, Wright MJ, et al. Genetic and environmental contributions to sleep-wake behavior in 12-year-old twins. Sleep. 2013;36(11):1715-1722. doi:10.5665/sleep.3136
121. Te Velde SJ, Van Der Aa N, Boomsma DI, et al. Genetic and environmental influences on individual differences in sleep duration during adolescence. Twin Res Hum Genet. 2013;16(6):1015-1025. doi:10.1017/thg.2013.74
122. Touchette E, Dionne G, Forget-Dubois N, et al. Genetic and environmental influences on daytime and nighttime sleep duration in early childhood. Pediatrics. 2013;131(6). doi:10.1542/peds.2012-2284
123. Watson NF, Buchwald D, Vitiello M V, Noonan C, Goldberg J. A twin study of sleep duration and body mass index. J Clin Sleep Med. 2010;6(1):11-17.
124. Paunio T, Korhonen T, Hublin C, et al. Longitudinal study on poor sleep and life dissatisfaction in a nationwide cohort of twins. Am J Epidemiol. 2009;169(2):206-213. doi:10.1093/aje/kwn305