Prenatal detection of cyclopia associated with interstitial deletion of 2p

Abstract

We report on a case of synophthalmic cyclopia and alobar holoprosencephaly associated with an interstitial deletion of the short arm of chromosome 2: del(2)(p21p23). This is the second case with this phenotype in association with deletion in this region, and comparison with the infrequent other cases of 2p deletions suggests a causal relationship between band 2p21 and cyclopia.

Interstitial deletion of the short arm of chromosome 2 in a mother and child, with facial dysmorphism and mild learning difficulties

“…Münke et al (1988) report a case with an apparently similar cytogenetic deletion as our case del(2)(p21p22.2) with alobar holoprosencephaly, synophthalmic cyclopia, proboscis above the eye, microcephaly and a short neck. Grundy et al (1989) found similar features in a stillborn infant with a slightly larger deletion del(2)(p21p23.3) (Fig. 1).…”

“…Unlike cases with a similar deletion, however, this case is not associated with holoprosencephaly and cyclopia (Münke et al, 1988;Grundy et al, 1989). Webb et al (1987) report a case with a de novo interstitial deletion of band 2p22 and a reciprocal translocation (3:7)(p21:q22).…”

Genomic Cloning, Structure, Expression Pattern, and Chromosomal Location of the HumanSIX3Gene

“…Holoprosencephaly type 2 (HPE 2; OMIM 157170) is a dominant human disorder that causes craniofacial malformations including cyclopia, midfacial defects, and absence of nasal bones. HPE 2 maps within the critical region defined by D2S119 and D2S288/D2S391 (8,9,19) and was previously suggested to be a disorder that could be caused by SIX3 (15). SIX3 is also a positional candidate gene for the autosomal dominant Malattia Leventinese (OMIM 126700) and the autosomal dominant Doyne honeycomb retinal dystrophy (DHRD; OMIM 126600), two disorders that could be allelic (caused by different mutations in the same gene).…”

Discordant Semilobar Holoprosencephaly in Monozygotic Twins with de novo inv dup(15) Marker Chromosome and de novo Mutation on SHH Gene

“…The most common chromosomal abnormality is trisomy 13. Other chromosome aberrations reported include ring chromosome 13 [8] , del (13q), and dup(13q) [9] ; trisomy 18, del (18)(p11.1 ] pter) [10] , and ring chromosome 18 [11]; trisomy 21 [12,13] , ring chromosome 21 [14] , and del(21)(q22.3) [15]; del(1)(q42 ] qter) [16]; del(2)(p21) [17,18] ; dup(3)(p21 ] pter) [19] ; trisomy 4p [20] and trisomy 4 [21] ; del(7)(q36) [22] ; del(9)(q32 ] qter) [23] ; del(11)(q21) mosaicism [24]; del (22) [29] .…”