1q21.1 microduplication: large verbal–nonverbal performance discrepancy and ddPCR assays of HYDIN/HYDIN2 copy number - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue npj Genomic Medicine Année : 2018

1q21.1 microduplication: large verbal–nonverbal performance discrepancy and ddPCR assays of HYDIN/HYDIN2 copy number

Résumé

Microduplication of chromosome 1q21.1 is observed in ~0.03% of adults. It has a highly variable, incompletely penetrant phenotype that can include intellectual disability, global developmental delay, specific learning disabilities, autism, schizophrenia, heart anomalies and dysmorphic features. We evaluated a 10-year-old-male with a 1q21.1 duplication by CGH microarray. He presented with major attention deficits, phonological dysphasia, poor fine motor skills, dysmorphia and mild autistic features, but not the typical macrocephaly. Neuropsychiatric evaluation demonstrated a novel phenotype: an unusually large discrepancy between non-verbal capacities (borderline-impaired WISC-IV index scores of 70 for Working Memory and 68 for Processing Speed) vs. strong verbal skills – scores of 126 for Verbal Comprehension (superior) and 111 for Perceptual Reasoning (normal). HYDIN2 has been hypothesized to underlie macrocephaly and perhaps cognitive deficits in this syndrome, but assessment of HYDIN2 copy number by microarray is difficult because of extensive segmental duplications. We performed whole-genome sequencing which supported HYDIN2 duplication (chr1:146,370,001-148,590,000, 2.22 Mb, hg38). To evaluate copy number more rigorously we developed droplet digital PCR assays of HYDIN2 (targeting unique 1 kb and 6 kb insertions) and its paralog HYDIN (targeting a unique 154 bp segment outside the HYDIN2 overlap). In an independent cohort, ddPCR was concordant with previous microarray data. Duplication of HYDIN2 was confirmed in the patient by ddPCR. This case demonstrates that a large discrepancy of verbal and non-verbal abilities can occur in 1q21.1 duplication syndrome, but it remains unclear whether this has a specific genomic basis. These ddPCR assays may be useful for future research on HYDIN2 copy number.
Fichier principal
Vignette du fichier
s41525-018-0059-2.pdf (956.63 Ko) Télécharger le fichier
Origine : Publication financée par une institution
Loading...

Dates et versions

hal-01974030 , version 1 (08-01-2019)

Identifiants

Citer

Jean Xavier, Bo Zhou, Frédéric Bilan, Xianglong Zhang, Brigitte Gilbert-Dussardier, et al.. 1q21.1 microduplication: large verbal–nonverbal performance discrepancy and ddPCR assays of HYDIN/HYDIN2 copy number. npj Genomic Medicine, 2018, 3 (1), pp.24. ⟨10.1038/s41525-018-0059-2⟩. ⟨hal-01974030⟩
88 Consultations
72 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More