Monogenik Obezite Ön Tanısı ile İncelenen Hastaların Klinik, Laboratuvar ve Genetik Sonuçlarının Değerlendirilmesi

Yıl 2021, Cilt: 19 Sayı: 1, 52 - 59, 09.04.2021

İlkay Ayrancı , Gönül Çatlı Berna Eroğlu Filibeli Elif Yiğit , Berk Özyılmaz Hayrullah Manyas Bumin N Dündar

Öz

Giriş: Şiddetli ve erken başlangıçlı obezitenin genetik nedenlerinde monogenik obezite formları önemli bir yer tutmaktadır. Bu çalışmada, kliniğimizde monogenik
obezite ön tanısı ile takip edilen olguların klinik ve moleküler genetik analiz sonuçlarının değerlendirilmesi amaçlanmıştır.

Gereç ve Yöntem: 2016-2018 yılları arasında kliniğimizde monogenik obezite ön tanısı ile moleküler genetik analiz yapılan olguların demografik, klinik ve
biyokimyasal verileri geriye yönelik incelendi ve kaydedildi.

Bulgular: Çalışmaya toplam 47 obez olgu (20 kız, 39 pubertal, ortalama yaş 14,3±3,2 yıl) alındı. Çalışmaya dahil edilen üç olguda MC4R’de patojenik varyant,
bir olguda veri tabanında patojen varyant olarak kabul edilmeyen LEPR’de heterozigot varyant saptandı. MC4R geninde sekans varyantı sıklığı %6,4, LEPR
geninde sekans varyantı sıklığı %2,1 olarak bulundu.

Sonuç: Çalışmamızda monogenik obezite şüphesiyle tetkik edilen çocukların %8,5’inde (n=4) sekans varyantı saptandı. Bu olgularda obezite yaşamın ilk bir
yılında gelişmişti ve ebeveynlerden en az birinde obezite mevcuttu. Bu nedenle, erken başlangıçlı obeziteye, ailesel obezite öyküsü eşlik ediyor ise ayırıcı tanıda
öncelikle monogenik obezite formlarından olan MC4R defekti düşünülmelidir.

Anahtar Kelimeler

Erken başlangıçlı,, monogenik obezite,, ailesel,

Evaluation of Clinical, Laboratory and Genetic Results of Patients Who Examined with a Pre-Diagnosis of Monogenic Obesity

Öz

Introduction:Monogenic forms of obesity have an important place in the genetic
causes of severe and early-onset obesity. In this study, it was aimed to evaluate the
clinical and molecular genetic analysis results of the cases followed up with a prediagnosis
of monogenic obesity in our clinic.
Materials and Methods: The demographic, clinical and biochemical data of the
patients had molecular genetic analysis with a pre-diagnosis of monogenic obesity
in our clinic between 2016 and 2018 were retrospectively analyzed and recorded.
Results: 47 obese cases (20 girls, 39 pubertal, mean age 14.3±3.2 years) were
included in the study. Pathogenic variant in MC4R was detected in three cases,
and heterozygous variant in LEPR, was not accepted as a pathogen variant in the
database in one case. The frequency of sequence variants in the MC4R gene was
6.4%, and the frequency of the sequence variants in the LEPR gene was 2.1%.
Conclusions: In our study, 8.5% (n=4) sequence variant was found in children
who were examined with suspicion of monogenic obesity. In these cases, obesity
developed in the first year of life and at least one parent had obesity. Therefore, if
early-onset obesity is accompanied by a family history of obesity, MC4R defect,
one of the monogenic obesity forms, should be considered in differential diagnosis.

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