Chromosome 11q13 homozygosity mapping. The top line indicates the region of homozygosity for a shared haplotype of a 13-Mb region in the families reported before.²  Several SNPs and an intronic deletion were identified. The private SNP in CALDAGGEF1 (c.1592-3C>A; reference sequence NM_001098670.1) and the small intronic deletion in NRXN2 gene (1872 bp between position 64227796 and 64229668, human reference sequence build 36.3). The position of the FERMT3 gene, the locus for LAD1v syndrome, is also indicated.