Dutch Reference Center for Prader-Willi Syndrome/Prader-Willi-like, Rotterdam, The Netherlands.
Department of Pediatrics, Subdivision of Endocrinology, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands.
Horm Res Paediatr. 2024;97(2):148-156. doi: 10.1159/000531629. Epub 2023 Jun 21.
Schaaf-Yang syndrome (SYS) is a rare neurodevelopmental disorder caused by truncating mutations of the MAGEL2 gene, located in the Prader-Willi syndrome (PWS) region. PWS and SYS have phenotypic overlap. Patients with SYS are often treated with growth hormone (GH), but evidence for the effectiveness of the treatment in patients with SYS is limited.
This study describes 7 children with SYS. We studied their phenotype, genotype, and the effect of GH treatment on height and body mass index (BMI) during 4 years and on body composition during 1 year.
All patients had a normal birth weight. Most patients had hypotonia and feeding difficulties after birth (86%). Full-scale IQ ranged from <50 to 92. All patients above the age of 2 years had psycho-behavioral problems. There were no apparent correlations between the phenotype and the location of the defect in the MAGEL2 gene. Mean (95% CI) height SDS increased significantly from -1.74 (-3.55; 0.07) at start to -0.05 (-1.87; 1.77) after 4 years of GH treatment. Mean (95% CI) BMI SDS decreased significantly from 2.01 (1.02; 3.00) to 1.22 (0.18; 2.26) after 6 months and remained the same during the rest of the follow-up. Fat mass percentage SDS decreased and lean body mass did not change during 1 year of treatment in 3 patients.
Patients presented with a phenotype of hypotonia, respiratory insufficiency, and feeding difficulties after birth, endocrine disorders, intellectual disability, and behavioral problems. Treatment with GH significantly improved height SDS and BMI over the course of 4 years.
Schaaf-Yang 综合征（SYS）是一种罕见的神经发育障碍，由 MAGEL2 基因的截断突变引起，该基因位于 Prader-Willi 综合征（PWS）区域。PWS 和 SYS 具有表型重叠。SYS 患者通常接受生长激素（GH）治疗，但 SYS 患者治疗效果的证据有限。
本研究描述了 7 例 SYS 患者。我们研究了他们的表型、基因型以及 GH 治疗对 4 年内身高和体重指数（BMI）的影响，以及 1 年内对身体成分的影响。
所有患者出生体重正常。大多数患者出生后存在低张力和喂养困难（86%）。智商（FIQ）评分均<50 至 92。所有 2 岁以上的患者均存在心理行为问题。MAGEL2 基因缺陷的位置与表型之间无明显相关性。GH 治疗 4 年后，平均（95%CI）身高 SDS 从治疗开始时的-1.74（-3.55；0.07）显著增加至-0.05（-1.87；1.77）。GH 治疗 6 个月后，平均（95%CI）BMI SDS 从 2.01（1.02；3.00）显著下降至 1.22（0.18；2.26），随访其余时间保持不变。3 例患者在治疗 1 年内，脂肪质量百分比 SDS 下降，瘦体重无变化。
患者表现为出生后低张力、呼吸功能不全、喂养困难、内分泌紊乱、智力残疾和行为问题。GH 治疗在 4 年内显著改善了身高 SDS 和 BMI。
