Abstract：
BACKGROUND: Trichotillomania (TTM) and excoriation disorder (ED) are impairing obsessive-compulsive related disorders that are common in the general population and for which there are no clear first-line medications, highlighting the need to better understand the underlying biology of these disorders to inform treatments. Given the importance of genetics in obsessive-compulsive disorder (OCD), evaluating genetic factors underlying TTM and ED may advance knowledge about the pathophysiology of these body-focused repetitive behaviors.
OBJECTIVE: In this systematic review, we summarize the available evidence on the genetics of TTM and ED and highlight gaps in the field warranting further research.
METHODS: We systematically searched Embase, PsycInfo, PubMed, Medline, Scopus, and Web of Science for original studies in genetic epidemiology (family or twin studies) and molecular genetics (candidate gene and genome-wide) published up to June 2023.
RESULTS: Of the 3536 records identified, 109 studies were included in this review. These studies indicated that genetic factors play an important role in the development of TTM and ED, some of which may be shared across the OCD spectrum, but there are no known high-confidence specific genetic risk factors for either TTM or ED.
CONCLUSIONS: Our review underscores the need for additional genome-wide research conducted on the genetics of TTM and ED, for instance, genome-wide association and whole-genome/whole-exome DNA sequencing studies. Recent advances in genomics have led to the discovery of risk genes in several psychiatric disorders, including related conditions such as OCD, but to date, TTM and ED have remained understudied.
OBJECTIVE: In this systematic review, we summarize the available evidence on the genetics of TTM and ED and highlight gaps in the field warranting further research.
METHODS: We systematically searched Embase, PsycInfo, PubMed, Medline, Scopus, and Web of Science for original studies in genetic epidemiology (family or twin studies) and molecular genetics (candidate gene and genome-wide) published up to June 2023.
RESULTS: Of the 3536 records identified, 109 studies were included in this review. These studies indicated that genetic factors play an important role in the development of TTM and ED, some of which may be shared across the OCD spectrum, but there are no known high-confidence specific genetic risk factors for either TTM or ED.
CONCLUSIONS: Our review underscores the need for additional genome-wide research conducted on the genetics of TTM and ED, for instance, genome-wide association and whole-genome/whole-exome DNA sequencing studies. Recent advances in genomics have led to the discovery of risk genes in several psychiatric disorders, including related conditions such as OCD, but to date, TTM and ED have remained understudied.
摘要：
背景：毛滴虫病（TTM）和割裂障碍（ED）损害了在普通人群中常见的强迫症相关疾病，并且没有明确的一线药物治疗，强调需要更好地了解这些疾病的潜在生物学，以告知治疗方法。鉴于遗传学在强迫症（OCD）中的重要性，评估TTM和ED背后的遗传因素可以提高对这些以身体为中心的重复行为的病理生理学的认识。
目的：在本系统综述中，我们总结了有关TTM和ED遗传学的现有证据,并强调了需要进一步研究的领域的空白.
方法：我们系统地搜索了Embase，PsycInfo,PubMed,Medline,Scopus,和WebofScience在遗传流行病学（家庭或双胞胎研究）和分子遗传学（候选基因和全基因组）方面的原始研究发表至2023年6月。
结果：在确定的3536条记录中，109项研究纳入本综述。这些研究表明遗传因素在TTM和ED的发生发展中起重要作用,其中一些可能在强迫症频谱中共享，但没有已知的TTM或ED的高置信度特异性遗传风险因素。
结论：我们的综述强调需要对TTM和ED的遗传学进行更多的全基因组研究，例如,全基因组关联和全基因组/全外显子组DNA测序研究。基因组学的最新进展导致在几种精神疾病中发现了风险基因，包括相关条件，如强迫症，但迄今为止,TTM和ED仍未得到充分研究。
目的：在本系统综述中，我们总结了有关TTM和ED遗传学的现有证据,并强调了需要进一步研究的领域的空白.
方法：我们系统地搜索了Embase，PsycInfo,PubMed,Medline,Scopus,和WebofScience在遗传流行病学（家庭或双胞胎研究）和分子遗传学（候选基因和全基因组）方面的原始研究发表至2023年6月。
结果：在确定的3536条记录中，109项研究纳入本综述。这些研究表明遗传因素在TTM和ED的发生发展中起重要作用,其中一些可能在强迫症频谱中共享，但没有已知的TTM或ED的高置信度特异性遗传风险因素。
结论：我们的综述强调需要对TTM和ED的遗传学进行更多的全基因组研究，例如,全基因组关联和全基因组/全外显子组DNA测序研究。基因组学的最新进展导致在几种精神疾病中发现了风险基因，包括相关条件，如强迫症，但迄今为止,TTM和ED仍未得到充分研究。
