Previdi Anaïk, Jordan Pénélope, Egloff Charles, Coussement Aurélie, Ahmed-Eli Samira, Tudal Laure, Bienvenu Thierry, Picone Olivier, Dupont Jean-Michel
APHP.Centre-Université Paris Cité, Site Hôpital Cochin, Service de Médecine Génomique des Maladies de Système et d'Organe, Paris, France.
AP-HP.Nord-Université Paris Cité, Site Hôpital Louis Mourier, Service de Gynécologie Obstétrique, Colombes, France.
Clin Genet. 2024 Nov;106(5):537-544. doi: 10.1111/cge.14592. Epub 2024 Jul 16.
15q24.1 microdeletion syndrome is a recently described condition often resulting from non-allelic homologous recombination (NAHR). Typical clinical features include pre and post-natal growth retardation, facial dysmorphism, developmental delay and intellectual disability. Nonspecific urogenital, skeletal, and digit abnormalities may be present, although other congenital malformations are less frequent. Consequently, only one case was reported prenatally, complicating the genotype-phenotype correlation and the genetic counseling. We identified prenatally a second case, presenting with cerebral abnormalities including hydrocephaly, macrocephaly, cerebellum hypoplasia, vermis hypoplasia, rhombencephalosynapsis, right kidney agenesis with left kidney duplication and micropenis. Genome-wide aCGH assay allowed a diagnosis at 26 weeks of amenorrhea revealing a 1.6 Mb interstitial deletion on the long arm of chromosome 15 at 15q24.1-q24.2 (arr[GRCh37] 15q24.1q24.2(74,399,112_76,019,966)x1). A deep review of the literature was undertaken to further delineate the prenatal clinical features and the candidate genes involved in the phenotype. Cerebral malformations are typically nonspecific, but microcephaly appears to be the most frequent in postnatal cases. Our case is the first reported with a frank cerebellar involvement.
15q24.1微缺失综合征是一种最近才被描述的病症,通常由非等位基因同源重组(NAHR)引起。典型的临床特征包括产前和产后生长发育迟缓、面部畸形、发育迟缓以及智力残疾。虽然其他先天性畸形较少见,但可能存在非特异性泌尿生殖系统、骨骼和手指异常。因此,产前仅报告过一例,这使得基因型与表型的相关性以及遗传咨询变得复杂。我们产前确诊了第二例,其表现为脑部异常,包括脑积水、巨头畸形、小脑发育不全、蚓部发育不全、菱形脑融合、右肾缺如伴左肾重复及小阴茎。全基因组aCGH检测在闭经26周时确诊,显示15号染色体长臂15q24.1 - q24.2处存在1.6 Mb的间质性缺失(arr[GRCh37] 15q24.1q24.2(74,399,112_76,019,966)x1)。我们对文献进行了深入回顾,以进一步阐明产前临床特征以及与该表型相关的候选基因。脑部畸形通常不具有特异性,但小头畸形在产后病例中似乎最为常见。我们的病例是首例报告有明显小脑受累的病例。