Question: How many tissue kallikrein genes are present in the human genome?

Context:
Tissue kallikreins are a group of closely related serine proteinases that are represented by multigene families in mice and rats.
Our map specifies the distance between genes to one base pair accuracy, the relative location, and the direction of transcription of all 15 genes.
The human tissue Kallikrein family consists of 15 genes with the majority shown to be differentially expressed in cancers and/or indicators of cancer prognosis.
The 15 members of the kallikrein-related serine peptidase (KLK) family have diverse tissue-specific expression profiles and putative proteolytic functions.
The 15 human and 24 mouse kallikreins have been implicated in pathophysiology of brain, kidney, and respiratory and reproductive systems and often are used as cancer biomarkers.
Kallikrein gene families have been identified previously in genomes of the human, the mouse, and the rat, and individual kallikrein-like genes have been found in many more species.
The human tissue kallikrein family of serine proteases (hK1-hK15 encoded by the genes KLK1-KLK15) is involved in several cancer-related processes.
The tissue kallikrein gene family consists of 15 genes tandemly arranged on human chromosome 19q13.4.
Human kallikreins are a cluster of 15 serine protease genes located in the chromosomal band 19q13.4, a non-randomly rearranged region in many solid tumors, including pancreatic cancer.
Tissue kallikrein genes (KLKs) are found on chromosome 19q13.3-4 as a gene cluster encoding 15 different serine proteases.
Project to perform in silico analyses of the expression pattern of the 15 human KLK genes in normal and cancerous ovarian tissues and cell lines.
Novel kallikrein genes were cloned recently, and it was shown that the human kallikrein family contains 15 genes tandemly aligned on chromosomal locus 19q13.3-q13.4.
The human kallikrein gene family consists of 15 serine proteases.
We have recently characterized the human kallikrein gene locus on chromosome 19q13.4, which includes 15 kallikrein genes.
The human tissue kallikrein and kallikrein-related peptidases (KLKs), encoded by the largest contiguous cluster of protease genes in the human genome, are secreted serine proteases with diverse expression patterns and physiological roles.
that forms the largest cluster of contiguous protease genes in the human genome.
Kallikrein-related peptidases (KLKs) constitute a family of 15 highly conserved serine proteases encoded by the largest uninterrupted cluster of protease-encoding genes within the human genome.
In this review, we describe the organization of the kallikrein locus and the structure of kallikrein genes and proteins.
The human tissue kallikrein gene family is the largest contiguous family of proteases in the human genome, containing 15 genes.
Human tissue kallikrein genes represent the largest contiguous group of proteases within the human genome.
Human tissue kallikreins (hKs), which are encoded by the largest contiguous cluster of protease genes in the human genome, are secreted serine proteases with diverse expression patterns and physiological roles.

Answer: Tissue kallikreins (KLKs) are a group of closely related serine proteinases that are represented by multigene families in the human genome. The human tissue kallikrein gene family consists of 15 genes, denoted KLK1–KLK15, tandemly arranged on chromosomal locus 19q13.4.
Exact answer: 15