The Association between GHRL and LEP Gene Polymorphisms and ADHD: Evidence from a Pediatric Cohort

Year 2025, Volume: 9 Issue: 2, 214 - 221, 31.08.2025

Ali Atabek Kilic , Nilfer Şahin , Aysegul Demirtas Bilgic , Çilem Özdemir , Murat Cenik , Tuba Edgünlü

Abstract

Aim: Dopaminergic neurons and dopamine transporters show variations in Attention Deficit Hyperactivity Disorder (ADHD). Furthermore,
Ghrelin and leptin, hormones recognized for their neurotrophic effects, are significant in central nervous system regulation, influencing
neuronal survival and development.
Material and Methods: This study aimed to examine the potential relationship between Attention Deficit Hyperactivity Disorder (ADHD) and
polymorphisms in the GHRL (rs34911341) and LEP (rs7799039) genes. The research sample consisted of 29 children diagnosed with ADHD
and 24 age-matched healthy controls. Genotypic analysis was conducted using the polymerase chain reaction-restriction fragment length
polymorphism (PCR-RFLP) technique.
Results: A significant difference in genotype distribution for the GHRL gene rs34911341 polymorphism was observed between the ADHD
group and healthy controls (p = 0.036), whereas allele frequencies did not show a statistically significant difference (p = 0.207). In contrast,
analysis of the LEP gene rs7799039 polymorphism revealed no significant differences in either genotype (p = 0.579) or allele frequencies (p
= 0.558) between the two groups.
Conclusion: These findings suggest a potential role for the GHRL rs34911341 polymorphism in the development or presentation of ADHD.
Further research is required to elucidate the mechanisms underlying this association.

Keywords

ADHD , Development , GHRL , LEP , polymorphism

Ethical Statement

The study protocol was approved by Muğla Sıtkı Koçman University Faculty of Medicine Medical Ethics Committee with the decision of 28/07/2021 and 16/I. The procedures used in this study adhere to the tenets of the Declaration of Helsinki. Informed consent. Written informed consent was obtained from all patients prior to their participation in the study.

Supporting Institution

This paper was supported by ‘Scientific and Technological Research Council of Turkey (TUBITAK)

Project Number

1919B012101939

Thanks

I would like to thank our research team and all the individuals and institutions who contributed to our study for their support and contributions.

GHRL ve LEP Gen Polimorfizmleri ile DEHB Arasındaki İlişki: Pediatrik Kohorttan Kanıtlar

Abstract

Amaç: Dopaminerjik nöronlar ve dopamin taşıyıcıları Dikkat Eksikliği Hiperaktivite Bozukluğu'nda (DEHB) farklılıklar gösterir. Ayrıca,
nörotrofik etkileriyle tanınan hormonlar olan Ghrelin ve leptin, nöronal sağ kalımı ve gelişimi etkileyerek merkezi sinir sistemi düzenlemesinde
önemlidir.
Gereç ve Yöntemler: Bu çalışmanın amacı, DEHB ile GHRL (rs34911341) ve LEP (rs7799039) polimorfizmleri arasındaki ilişkiyi araştırmaktır.
Çalışmaya DEHB tanısı almış 29 çocuk ve 24 sağlıklı çocuk dahil edildi. Genotipleme, PCR-RFLP (polimeraz zincir reaksiyonu-restriksiyon
parça uzunluğu polimorfizmi) yöntemi aracılığıyla gerçekleştirildi.
Bulgular: GHRL geni rs34911341 polimorfizminin genotip sıklığı, DEHB ve sağlıklı kontrol grupları arasında önemli ölçüde farklılık gösterdi
(p=0,036), ancak alel sıklıkları önemli ölçüde farklılık göstermedi (p=0,207). LEP rs7799039 polimorfizmi için, iki grup arasında ne genotip
ne de alel frekansları farklı değildi (genotip frekansı için p=0,579; alel frekansı için p=0,558).
Sonuç: Bu bulgular, GHRL rs34911341 polimorfizminin DEHB'nin gelişiminde veya sunumunda potansiyel bir rolü olduğunu göstermektedir.
Bu ilişkinin altında yatan mekanizmaları açıklamak için daha fazla araştırma gerekmektedir.

Keywords

DEHB , Gelişim , GHRL , LEP , polimorfizm

Ethical Statement

Çalışma protokolü Muğla Sıtkı Koçman Üniversitesi Tıp Fakültesi Tıbbi Etik Kurulu'nun 28/07/2021 tarihli ve 16/I sayılı kararıyla onaylandı. Bu çalışmada kullanılan prosedürler Helsinki Bildirgesi ilkelerine uygundur. Bilgilendirilmiş onam. Çalışmaya katılmadan önce tüm hastalardan yazılı bilgilendirilmiş onam alındı.

Supporting Institution

Bu makale 'Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK)' tarafından desteklenmiştir.

Project Number

1919B012101939

Thanks

Araştırma ekibimize ve çalışmamıza katkı sağlayan tüm kişi ve kurumlara destek ve katkılarından dolayı teşekkür etmek isterim.

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