Guidelines for UPD testing

 

·         CCMG:

·         Recommend post-natal UPD testing:

·         Individuals with multiple congenital anomalies, developmental delay / mental retardation with:

·         Balanced Robertsonian involving 14 or 15 (both familial and de novo)

·         Marker derived from 14 or 15 containing no apparent euchromatic material

·         neonatal diabetes mellitus

·         clinical features suggestive of maternal or paternal UPD14

·         homozygous for an autosomal recessive disease, but only one parent is a carrier

·         first exclude non-paternity, heterozygous deletion, testing artifact

·         female homozygous for X-linked disorder

·         male with apparent father-son transmission of X-linked disorder

·         Consider postnatal UPD testing:

·         Multiple congenital anomalies, developmental delay / mental retardation, with:

·         Translocation between any chromosome known to carry imprinted genes

·         Recommend prenatal UPD testing:

·         Balanced Robertsonian involving 14 or 15 (familial or de novo)

·         Isochromosome of 14 or 15 (familial or de novo)

·         ESAC with no apparent euchromatic material derived from 14 or 15 (de novo)

·         Parent is a carrier of a balanced Robertsonian involving 14 or 15 (even with normal karyotype)

·         Level II or level III mosaicism for trisomy or monosomy of chromosomes 6, 7, 11, 14, or 15

·         Consider prenatal UPD testing:

·         Translocation involving 6, 7, 11, 14, or 15

·         Ultrasound anomalies consistent with a UPD phenotype

·         Not an indication for UPD testing:

·         History of a child with UPD alone

·         ACMG – individuals in whom testing should be considered:

·         Complete trisomy for chromosomes 6,7,11,14, or 15.

·         Level II or level III mosaicism on CVS for chromosomes 6,7,11,14, or 15

·         Level II mosaicism on amniotic fluid for 6,7,11,14, or 15

·         Robertsonian translocation involving 14 or 15

·         (familial or de novo)

·         Isochromosome involving 14 or 15

·         Features of UPD syndromes

·         Neonatal diabetes mellitus

·         BWS with normal karyotype and no dup(11p15.5 by FISH

·          

 

References:

·         Shaffer LG, Agan N, Goldberg JD, et al. American College of Medical Genetics statement of diagnostic testing for uniparental disomy. Genet. Med. 2001;3(3):206-211.

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