A total of six TGMS (thermosensitive genic male sterile lines) and nine pollinator lines were subjected to molecular characterization using 48 genome-wide SSR (simple sequence repeat) markers. Cluster analysis revealed clear differentiation among the TGMS lines according to their source of origin. The SSR-based genetic distance between the hybrids of the parental lines ranged from 0.36 to 0.79 suggesting a high degree of genetic divergence. Among a set of 54 hybrids generated using parental lines, 32 showed better parent heterosis (+21.7%) while 19 showed mid-parent heterosis (+15.0%). For the trait yield per plant genetic distance (GD) was negatively correlated with F1 performance (r = -0.202), mid-parent heterosis (r = -0.325*; P < 0.05), and better parent heterosis (r = -0.261), while it was positively correlated with specific combining ability (r = 0.042). Based on the grouped genetic distance (GGD), the hybrid combinations were divided into four groups. The GGD showed linear correlation with hybrid performance within the group (GGD = 40 -50: r = -0.07; GGD = 70 -80: r = 0.32). This information can be utilized in the development of higher yielding, two-line rice hybrids through selection of intermediately diverse parental lines using GGD.

Genetic diversity among four wild mango species and 29 genotypes/cultivars of polyembryonic and monoembryonic mangoes of the Andaman Islands were analysed using inter simple sequence repeat (ISSR) markers. A total of 335 ISSR markers were scored, of which 213 markers were polymorphic. These markers were used to estimate the genetic similarity among accessions using a Dice similarity coefficient. Similarity values ranged between 2Á70% with an average of 34%. A similarity matrix was used to construct a dendrogram and principle coordinator plot to show genetic relationships among accessions. The sampled genotypes/accessions were divided into three prominent groups of 4, 16 and 13, differentiating the polyembryonic genotypes from monoembryonic genotypes and wild mango species. The study provides further information on the evolution and diversity of the mango accessions of the island ecosystem. The analysis also separates the differentially flowering polyembryonic genotypes from the early flowering monoembryonic types for their exploitation in genetic improvement programmes or selection in the regions of tropical island ecosystems where the attribute of early flowering can be effectively utilised.

A set of morphological traits and SSR markers were used to determine the genetic relationship among 12 elite thermosensitive genic male sterile (TGMS) lines developed at three different research institutions of India. Agro-morphological data recorded on 20 morphological traits revealed a wide base of genetic variation and a set of four morphological traits could distinguish most of the TGMS lines. Analysis with 30 SSR markers (20 EST-SSRs and 10 genomic SSRs) revealed 27 markers to be polymorphic, amplifying a total of 83 alleles. Each SSR marker amplified 2-6 alleles with an average of 2.76 alleles per marker and a PIC value varying from 0.54 to 0.96. Cluster analysis based on SSR and morphological data clearly differentiated the lines according to their source of origin. Correlation analysis between morphological and molecular data revealed a very poor association (r = 0.06), which could be attributed to selection pressure, genetic drift, sampling error and unknown relationship among related lines. The SSR markers discriminated the genotypes distinctly and quantified the genetic diversity precisely among the TGMS lines. Data on the yield per plant indicated that the genotypes grouping under a similar cluster showed same heterotic behaviour as compared to the genotypes from different clusters when crossed to similar pollinators.

Jawad syndrome is a multiple congenital anomaly and intellectual disability syndrome with mutation in RBBP8 reported only in two families. Here, we report on two new families from Pakistan and identified a previously reported variant in RBBP8, NM_002894.3:c.1808‐1809delTA. We could show that this mutation impairs splicing resulting in two different abnormal transcripts. Finally, we could verify a shared haplotype among all four families and estimate the founder event to have occurred some 24 generations ago.

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